Question 1

Kaolin is chemically classified as

Accepted Answer

argillaceous rock

Question 2

Initial setting time of cement for asbestos cement products should be not less than

Accepted Answer

90 minutes.

Question 3

The rocks which are formed due to cooling of magma at a considerable depth from earth's surface are called

Accepted Answer

Plutonic rocks

Question 4

For the manufacture of Portland cement, the proportions of raw materials used, are

Accepted Answer

lime 63% ; silica 22% ; other ingredients 15%

Question 5

Ultimate strength to cement is provided by

Accepted Answer

Di-calcium silicate

Question 6

Which one of the following is acid resistant asbestos:

Accepted Answer

All the above.

Question 7

Sewer pipes are made of

Accepted Answer

stone ware

Question 8

Paints and finishes — varnish is defined as a transparent or semi-transparent protective coating consisting of resinous substances dissolved or carried in which of the following media?

Accepted Answer

Introduction / Context:In building materials and architectural finishes, varnish is a clear or lightly tinted coating used to protect and enhance the appearance of wood, metals, and some masonry surfaces. Understanding what a varnish is made of (resins plus an appropriate vehicle/solvent or oil) helps you choose the right product for durability, drying time, and visual effect. Given Data / Assumptions: The question asks which media can serve in a varnish system for dissolving or carrying resinous substances. Traditional and modern varnishes include spirit varnishes, oil varnishes, and turpentine/solvent-borne types. Terminology in civil engineering exams often groups vehicles (drying oils) and solvents as acceptable carriers for resins. Concept / Approach: Varnish fundamentally contains a resin (natural or synthetic) plus a vehicle (drying oil and/or solvent) that enables application and forms a film after drying/curing. Spirit varnishes dissolve resins in alcohol (e.g., shellac). Oil varnishes dissolve resins in a drying oil such as linseed oil, sometimes with additional solvent for brushability. Turpentine and similar hydrocarbons act as solvents that thin and carry resins or resin-oil blends, evaporating after application. Step-by-Step Solution: 1) Recognize that varnish = resin + vehicle (oil and/or solvent).2) Spirit varnish example: resin (e.g., shellac) + alcohol → fast-drying clear film.3) Oil varnish example: resin + linseed oil (a drying oil) → oxidative cure, durable film.4) Solvent-borne varnish example: resinous solution thinned with turpentine for application.5) Therefore, all three listed carriers/media are valid in varnish systems. Verification / Alternative check: Traditional finishing manuals classify varnishes into spirit (alcohol-based), oil (linseed/tung based), and resin-solvent blends (often reduced with turpentine or mineral spirits), confirming the breadth of acceptable media. Why Other Options Are Wrong: Choosing only one of alcohol, linseed, or turpentine would exclude other standard varnish types; the correct holistic choice is all the above. Common Pitfalls: Confusing varnishes with paints (which contain pigments) or with lacquers (thermoplastic resins re-dissolvable in solvents). Also, forgetting that linseed acts as a vehicle (binder) rather than a mere solvent. Final Answer: all the above

Question 9

Polymer materials — plastics made from cellulose-based resins (e.g., cellulose acetate) typically exhibit which combination of properties relevant to engineering and electrical uses?

Accepted Answer

Introduction / Context:Cellulose-derived plastics such as cellulose acetate, cellulose acetate butyrate (CAB), and cellulose nitrate historically found wide use in glazing, films, tool handles, and electrical components. Recognizing their property profile helps in selecting materials for transparency, toughness, and insulation tasks in civil and electrical installations. Given Data / Assumptions: Cellulose resins can be compounded for clarity and mechanical strength. Electrical properties refer to dielectric strength and insulation resistance. Question seeks whether these properties can be achieved simultaneously. Concept / Approach: Cellulose acetate and related resins form clear thermoplastics with good optical transmission—often used where glass-like clarity and shatter resistance are desirable. They also offer useful toughness and impact resistance compared with brittle thermosets. Electrically, they are non-conductive and provide good dielectric behavior, making them suitable for insulating housings and components (within their temperature limits). Thus, all three property statements are valid for cellulose plastics when properly formulated and processed. Step-by-Step Solution: 1) Identify the base polymer family: cellulose esters.2) Note optical clarity: high visible light transmission with good haze control.3) Assess mechanics: adequate tensile strength and impact toughness for typical components.4) Assess electrical behavior: high resistivity and dielectric strength at room temperature.5) Conclude that all listed statements are true together. Verification / Alternative check: Material data sheets for cellulose acetate show transparency (∼90% transmittance), tensile strength in the tens of MPa, and dielectric strength suitable for many low-voltage uses. Why Other Options Are Wrong: Choosing only one property ignores the broad, well-documented capability of cellulose resins; the comprehensive answer is All the above. Common Pitfalls: Confusing cellulose nitrate (flammable) with less flammable cellulose acetate; overlooking temperature sensitivity which limits high-heat applications. Final Answer: All the above

Question 10

Concrete technology — select the correct recommendations for water–cement ratio (by weight) for various structural conditions, including wetting/drying cycles and continuous underwater exposure, for thin and massive sections.

Accepted Answer

Introduction / Context:The water–cement (w/c) ratio is the single most influential parameter controlling strength, permeability, durability, and shrinkage of concrete. Codes and textbooks provide indicative limits for different exposure conditions and member thicknesses. This question consolidates typical recommendations for thin versus mass concrete and for structures in alternating wet/dry service or completely submerged service. Given Data / Assumptions: Thin sections have greater surface-to-volume ratio and are more prone to rapid moisture exchange. Mass concrete develops heat and has lower surface exposure per unit volume. Wetting/drying cycles are more severe for durability than continuous submersion (due to repeated ingress/egress of water and salts). Concept / Approach: Lower w/c ratios improve durability and strength but may reduce workability if not compensated by admixtures. For wetting and drying exposures, particularly in thin members, a stricter (lower) w/c such as 0.45 is recommended. For mass concrete under similar exposure, a somewhat higher figure (≈0.55) is often acceptable. In continuous underwater conditions, thin members may use ≈0.55; massive members can tolerate ≈0.65 due to reduced salt crystallization cycling and different thermal considerations, while still meeting strength requirements. Collectively, these are widely taught indicative values. Step-by-Step Solution: 1) Map exposure severity: wet/dry cycling > continuous submersion (for many durability mechanisms).2) Map member type: thin sections demand tighter w/c due to higher permeability path lengths and drying.3) Assign w/c limits accordingly: 0.45 (thin, wet/dry); 0.55 (mass, wet/dry); 0.55 (thin, submerged); 0.65 (mass, submerged).4) Conclude that each individual statement is consistent, hence “All the above”. Verification / Alternative check: Durability guidance in many curricula reflects similar tiers of w/c limits depending on exposure and element size, supporting the listed values. Why Other Options Are Wrong: Picking any single statement ignores the complete, context-based mapping the question requests; all four apply to the stated conditions. Common Pitfalls: Assuming a single “magic” w/c suits every exposure; neglecting that admixtures/supplementary cementitious materials can permit lower permeability at practical slumps. Final Answer: All the above

Question 11

Ferrous metallurgy — wrought iron contains carbon up to approximately what percentage by mass?

Accepted Answer

Introduction / Context:Classifying ferrous metals by carbon content is fundamental to understanding their properties and applications. Wrought iron is historically produced by repeated working of low-carbon iron with slag stringers, yielding excellent ductility and corrosion resistance but low hardenability and strength compared with steels and cast irons. Given Data / Assumptions: The question seeks the upper limit of carbon content in wrought iron. Exam conventions often round values to simple percentages. Other constituents (slag, phosphorus) may be present in small amounts. Concept / Approach: Wrought iron is very low carbon, traditionally cited as containing up to about 0.08–0.15% C in many references; however, civil engineering question banks commonly accept an upper limit of “about 0.25%”. Values of 1.0%, 1.5%, or 2% carbon would place the material well into the steel or cast iron ranges, fundamentally changing microstructure and properties. Step-by-Step Solution: 1) Recall ferrous ranges: wrought iron (very low C), steel (~0.02–2.1% C), cast iron (≈2–4% C).2) Compare options with these bands.3) Only 0.25% lies in the conventional “upper bound” often stated for wrought iron in exams.4) Select 0.25% as the best match. Verification / Alternative check: Historic metallurgy texts and exam preparatory materials align wrought iron with a very low carbon content, typically cited below a quarter percent in rounded figures. Why Other Options Are Wrong: 1.0% or 1.5% — firmly within high-carbon steels; 2% — cast iron territory; these would drastically reduce ductility and alter processing. Common Pitfalls: Confusing wrought iron with mild steel; ignoring slag inclusions that impart characteristic fibrous appearance without raising carbon content. Final Answer: 0.25%

Question 12

Binders and cements — the initial setting time of lime–pozzolana binder (used in mortars and low-heat concretes) is approximately:

Accepted Answer

Introduction / Context:Lime–pozzolana binders (using hydrated lime with reactive siliceous/aluminous pozzolana) develop strength through pozzolanic reactions forming C-S-H and related hydrates. Knowing their initial setting time is important for mixing, transport, and placing schedules, especially in heritage conservation and low-heat applications where Portland cement is not preferred. Given Data / Assumptions: Standard laboratory conditions are assumed (normal temperature and humidity). Initial setting time refers to the onset of rigidity measured by needle penetration methods. Typical formulations of lime–pozzolana binder are considered (not rapid-hardening blends). Concept / Approach: Compared with ordinary Portland cement (OPC), which must not set in less than 30 minutes per standards, lime–pozzolana systems tend to set more slowly because the reaction depends on the availability of dissolved silica/alumina and lime. A commonly cited benchmark for initial set is about 60 minutes, allowing adequate working time while ensuring early stability for finishing operations. Step-by-Step Solution: 1) Identify binder type: lime + pozzolana (e.g., volcanic ash, fly ash, surkhi).2) Note reaction kinetics: slower than OPC; setting governed by gel formation.3) Select an initial set consistent with practice—about 60 minutes.4) Confirm suitability: provides workable time window without undue delay. Verification / Alternative check: Conservation and traditional construction guidelines often cite ∼1 hour as a practical initial set for lime–pozzolana mixes, though exact values vary with fineness, temperature, and mix proportions. Why Other Options Are Wrong: 30 minutes — more typical of OPC minimum; too short for many lime–pozzolana mixes.90 or 120 minutes — possible in cool conditions but generally longer than the common benchmark used in exam contexts. Common Pitfalls: Assuming all binders follow OPC times; ignoring environmental effects that can extend or shorten set times. Final Answer: 60 minutes

Question 13

Alloy steels — a common austenitic stainless steel composition widely used in construction hardware and kitchen equipment contains approximately which chromium and nickel percentages?

Accepted Answer

Introduction / Context:Austenitic stainless steels are prized for corrosion resistance and formability. The most ubiquitous grade family is the “18/8” composition (e.g., AISI 304), referenced by its approximate chromium and nickel content, which stabilizes the austenitic phase and provides robust passivation behavior in atmospheric and many aqueous environments. Given Data / Assumptions: The question targets the iconic “18/8” stainless composition. Minor elements (C, Mn, Si, N, Mo) are not central to this identification. Percentages are approximate nominal values used in teaching. Concept / Approach: Chromium at about 18% forms a stable, self-healing chromium oxide passive film that confers corrosion resistance. Nickel at about 8% stabilizes austenite, improving ductility and toughness, especially at low temperatures, and aiding formability and weldability. This combination is a standard reference point for stainless steels in civil/architectural hardware, food processing equipment, and household applications. Step-by-Step Solution: 1) Recall the shorthand “18/8” for common austenitic stainless steel.2) Map 18 → chromium and 8 → nickel.3) Select the option that matches these values.4) Confirm its prevalence in AISI 304/304L families. Verification / Alternative check: Standards and material datasheets consistently list Cr ≈ 18% and Ni ≈ 8% (ranges allowed) for AISI 304-type steels. Why Other Options Are Wrong: Other combinations either invert or greatly exaggerate Ni/Cr levels and do not represent the mainstream austenitic grades. Common Pitfalls: Confusing 18/8 (304) with molybdenum-bearing 316 (≈18% Cr, 10–12% Ni, 2–3% Mo). Final Answer: 18% of chromuim and 8% nickel

Question 14

Brickmaking practice — for large projects, excavated brick clay is commonly dug and left to weather (to slake, mellow, and homogenize) throughout which season before tempering and molding?

Accepted Answer

Introduction / Context:Good bricks depend on suitable clay preparation. Weathering—exposing dug clay to the elements—helps break down lumps, oxidize organics, and improve workability. Large-scale brickworks plan excavation and weathering around seasonal cycles to achieve consistent plasticity and reduced lime nodules/organic contaminants before tempering and molding. Given Data / Assumptions: Project scale permits stockpiling and extended natural weathering. Climatic pattern includes a distinct rainy season (monsoon). Objective is to improve clay quality without intensive mechanical processing. Concept / Approach: During the monsoon, rainfall and wet-dry cycling assist in slaking and mellowing the clay. Water infiltrates, dissolves soluble salts, and breaks down clay aggregates. Microbial activity and oxidation help decompose organic matter. After the monsoon, the clay can be tempered with controlled water content and thoroughly mixed for molding, yielding more uniform bricks with fewer defects (e.g., blisters from unburnt organics or lime pops). Step-by-Step Solution: 1) Excavate clay from borrow pits ahead of the production season.2) Spread and stockpile to allow exposure to rain and air during monsoon months.3) After weathering, temper and pug the clay to a homogeneous plastic mass.4) Proceed with molding, drying, and firing. Verification / Alternative check: Traditional brickmaking manuals recommend monsoon weathering for improved plasticity and reduced impurities, especially in South Asian contexts. Why Other Options Are Wrong: Winter or summer alone lack the sustained wetting critical for slaking; “none of these” conflicts with established practice. Common Pitfalls: Skipping weathering to save time, leading to higher reject rates; inadequate drainage of stockpiles causing contamination or leaching losses. Final Answer: the monsoon

Question 15

Steelmaking processes — choose the correct statements regarding heat supply and oxidation mechanisms in basic Bessemer, open-hearth (Siemens–Martin), and Siemens processes.

Accepted Answer

Introduction / Context:Classic steelmaking routes include the Bessemer converter and the open-hearth (Siemens–Martin) furnace. Understanding where heat comes from and how oxidation occurs is foundational to process classification and historical exam questions. Each method relies on different thermal balances and oxidants to refine pig iron into steel. Given Data / Assumptions: “Basic Bessemer” refers to the basic-lined (Thomas) converter variant. Open-hearth refers to regenerative, reverberatory furnaces (Siemens–Martin). “Siemens process” here alludes to Siemens–Martin practice using ore as an oxidant. Concept / Approach: In the Bessemer converter, oxidation of impurities within the metal (C, Si, Mn, P in the basic process) releases substantial heat, so the metal itself supplies the heat to keep the bath molten—colloquially phrased as “the steel heats the converter.” In the open-hearth process, the furnace (regeneratively heated by preheated air/gas) supplies external heat to the steel bath. In Siemens–Martin practice, iron ore can be charged to provide oxygen, oxidizing impurities in pig iron to refine the metal. Therefore, all three statements are acceptable in the standard exam framing. Step-by-Step Solution: 1) Recognize exothermic oxidation in Bessemer provides in-bath heat.2) Identify external firing and regenerative heating in open-hearth furnaces.3) Note the role of added ore as an oxidant in Siemens–Martin steelmaking.4) Conclude each statement is correct → choose “all the above”. Verification / Alternative check: Metallurgical histories and process descriptions corroborate these simplified distinctions between converter and open-hearth operations. Why Other Options Are Wrong: Selecting only (a), (b), or (c) omits other equally true statements, making “all the above” the comprehensive choice. Common Pitfalls: Interpreting (a) too literally: it means heat is generated in the bath, not that solid steel is a fuel. Also, not distinguishing between acid and basic linings in Bessemer practice. Final Answer: all the above

Question 16

Waterproofing and damp-proofing — bitumen felt used in building construction is correctly described by which of the following statements?

Accepted Answer

Introduction / Context:Bitumen felt (roofing felt) is a common membrane material in civil engineering for preventing water ingress through roofs, terraces, and walls. Understanding its composition and uses clarifies where it fits within a building’s moisture control strategy (waterproofing versus damp-proofing). Given Data / Assumptions: Traditional felt uses a fibrous base (e.g., hessian/jute or fiberglass) saturated/impregnated with bitumen. Applications include membranes below screeds, on parapets, and as DPC courses. The question allows multiple correct descriptions. Concept / Approach: Bitumen felt is a composite sheet formed by saturating a fabric (historically hessian; modern versions may use polyester or glass mat) with bitumen, sometimes with mineral surfacing. It is used both for waterproofing (resisting liquid water under some hydrostatic pressure) and for damp-proofing (blocking capillary moisture without significant head), depending on grade, layers, and detailing. Thus, all statements collectively describe the material’s nature and uses. Step-by-Step Solution: 1) Identify composition: fibrous mat + bitumen impregnation.2) Map to functions: roofing membranes (waterproofing) and DPC courses (damp-proofing).3) Confirm historical use of hessian fibres as the base fabric.4) Conclude that all provided statements are correct together. Verification / Alternative check: Standard specifications list bituminous felts for horizontal and vertical damp-proof courses and multi-ply roofing systems, validating all statements. Why Other Options Are Wrong: Choosing any single statement would omit key aspects of either use or composition; “all the above” is therefore accurate. Common Pitfalls: Assuming one-ply felt equals full waterproofing in all conditions; proper multi-ply build-ups and protection layers are essential for durability. Final Answer: all the above

Question 17

Stonework practice — choose the correct statements regarding the placement of natural beds (bedding planes) of sedimentary stones in arches, cornices, and walls for structural performance and durability.

Accepted Answer

Introduction / Context:For sedimentary stones such as sandstone and limestone, the natural bed (stratification plane) is the plane along which the stone was originally deposited. Correct orientation of this bed in construction affects load-carrying capacity, weathering resistance, and crack control in arches, cornices, and walls. Given Data / Assumptions: Sedimentary stones exhibit different strengths parallel and perpendicular to bedding. Arches, cornices, and walls impose distinct stress and weathering conditions. Traditional stonemasonry rules of thumb apply. Concept / Approach: Arches: Voussoirs work largely in compression along radial lines; placing natural beds radially keeps layers in compression and reduces delamination. Cornices: These project outward; placing the natural bed vertical minimizes shearing along bedding due to the cantilever action and improves weathering resistance of exposed horizontal surfaces. Walls: For stacked masonry under vertical loads, stones should generally be laid with the natural bed horizontal (as they were in nature) to ensure maximum stability and reduce the risk of spalling along bedding planes. Step-by-Step Solution: 1) Consider stress paths for each element type (arch, cornice, wall).2) Align bedding planes to keep them in compression or least stressed orientation.3) Apply the conventional rules: radial (arch), vertical (cornice), horizontal (wall).4) Select “All the above” as all statements match best practice. Verification / Alternative check: Historical stonemasonry texts and building conservation guidance echo these orientations to maximize durability and structural reliability of sedimentary stones. Why Other Options Are Wrong: Choosing only one orientation ignores the different load cases; all three are context-correct. Common Pitfalls: Using a single rule for all elements; disregarding that igneous/metamorphic stones may behave more isotropically than sedimentary stones. Final Answer: All the above

Question 18

Ironmaking practice: If a blast furnace (or cupola) operates with insufficient fuel at relatively low temperatures and poor silicon reduction, which variety of pig iron is typically produced under these chilled conditions?

Accepted Answer

Introduction / Context: Pig iron tapped from a blast furnace is classified by appearance and chemistry into grey, mottled, and white varieties. These categories reflect carbon form (graphite vs. cementite) and the thermal/chemical conditions prevailing during smelting and solidification. Understanding how fuel rate and temperature affect the product is fundamental in ironmaking and foundry practice. Given Data / Assumptions: Furnace is run with insufficient fuel (low coke rate) resulting in lower hearth temperatures. Reduced silicon pickup and relatively rapid chilling during solidification. Standard ironmaking inputs (ore, flux, coke) otherwise unchanged. Concept / Approach: Higher furnace temperatures and adequate silicon promote graphite formation, yielding grey pig. Conversely, low thermal conditions favor carbon remaining combined as iron carbide (Fe3C), producing a hard, white fracture—white (forge) pig. Intermediate conditions yield mottled pig with mixed graphite and cementite areas. Thus, fuel-starved, cooler operation biases the product toward the white variety. Step-by-Step Solution: 1) Note operating state: low fuel → low flame temperature.2) Infer chemistry: lower Si and slower graphitization kinetics.3) Predict solidification structure: cementite-rich matrix → white fracture.4) Map to nomenclature: white or forge pig. Verification / Alternative check: Foundry texts relate white iron formation to rapid cooling and low silicon; both occur when furnaces are run cool or the stream is chilled, matching the stated condition. Why Other Options Are Wrong: Grey or foundry pig: requires hotter furnace and higher silicon to promote graphite flakes. Mottled pig: intermediate case, not the extreme cool, fuel-poor condition described. Bessemer pig / Basic (Thomas) pig: terms tied to converter suitability (impurity levels), not the chilled appearance caused by low furnace temperature. Common Pitfalls: Confusing ‘‘white’’ structure (cementite) with merely low carbon content; total C can still be high but in combined form. Attributing white iron solely to quenching; process temperature and silicon also govern. Final Answer: White or forge pig

Question 19

Bituminous materials identification: Match bitumen's physical state to its common naming in civil engineering materials—solid, semi-fluid, and fluid—used for roads and waterproofing applications.

Accepted Answer

Introduction / Context: Civil engineers frequently encounter bituminous binders in different physical forms depending on temperature and processing. Recognizing the conventional names associated with each state helps in selecting materials for paving, damp-proofing, and crack sealing. Given Data / Assumptions: ‘‘Bitumen’’ broadly covers hydrocarbon binders obtained from petroleum and natural sources. Conventional classroom terminology associates states with legacy names. Focus is on generic naming used in many MCQs and handbooks. Concept / Approach: In many traditional texts, solid bitumen used for paving is generically called asphalt (natural or petroleum asphalt). Semi-fluid forms—historically produced from coal or petroleum distillates—are termed mineral tar. Very fluid hydrocarbons in the bituminous family are often linked to petroleum fractions. Though modern specifications distinguish between petroleum bitumen and coal tar, the question follows the conventional mapping and therefore invites the combined choice ‘‘all the above.’’ Step-by-Step Solution: 1) Identify each state and its traditional label.2) Confirm all three pairings are standard in classic teaching materials.3) Select the comprehensive option. Verification / Alternative check: Older road-materials references list asphalt (solid paving grade), mineral tar (semi-fluid), and petroleum (fluid) as state descriptors, despite today’s finer specification (penetration/viscosity grades, cutbacks, and emulsions). Why Other Options Are Wrong: Selecting only one pairing omits the remaining correct associations, while the item expects the full set. Coal-tar pitch (fluid) is inaccurate; pitch is typically more viscous/solid at ambient conditions. Common Pitfalls: Confusing modern specification language with legacy teaching terms; this question uses the latter. Mixing coal-tar and petroleum-asphalt terminology indiscriminately. Final Answer: all the above

Question 20

Polymer materials overview: Which statements correctly characterize ‘‘plastics’’ as used in engineering applications, with respect to composition, behavior under heat/pressure, and finished product properties at room temperature?

Accepted Answer

Introduction / Context: ‘‘Plastic’’ is a broad term for organic polymeric materials (thermoplastics and thermosets) compounded with additives. Their processing and performance underpin countless engineering components—from housings to structural composites—making a clear understanding of definitions essential. Given Data / Assumptions: Plastics include thermoplastics (e.g., PE, PP, PVC) and thermosets (e.g., epoxies, phenolics). Additives: fillers, plasticizers, stabilizers, pigments, and reinforcements. ‘‘Rigid and stable’’ refers to many finished articles at room temperature (though some formulations are flexible). Concept / Approach: Plastics are typically organic (carbon-based) macromolecules acting as binders that hold fillers/reinforcements. Under appropriate heat and pressure, they flow (thermoplastics soften and reflow; thermosets flow during cure and then crosslink). After cooling/cure, many products are dimensionally stable and rigid at ambient conditions, suitable for service in appliances, automotive parts, and building products. Step-by-Step Solution: 1) Identify plastic as organic polymer matrix materials.2) Confirm processing behavior: flow under heat/pressure (molding, extrusion).3) Note finished performance: adequate rigidity and stability for designed use. Verification / Alternative check: Standards and handbooks define plastics as organic high-molecular-weight materials that can be shaped by flow and retain form at room temperature, consistent with all listed statements. Why Other Options Are Wrong: Each individual statement is true; therefore the umbrella option ‘‘All the above’’ captures the complete definition. Common Pitfalls: Assuming all plastics are rigid—some are elastomeric; the statement allows for typical rigid finished goods without excluding flexible grades. Confusing thermoplastic reprocessability with thermoset irreversibility after cure. Final Answer: All the above

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