Difficulty: Hard
Correct Answer: 9.71 cm
Explanation:
Introduction / Context:Conservation of volume applies when reshaping solids. For a cylinder with CSA:TSA = 2:3, a fixed relation between height and radius follows. Combine with volume equality from the original hemisphere.
Given Data / Assumptions:
Concept / Approach:From CSA:TSA = 2:3 ⇒ h : (h + r) = 2 : 3 ⇒ h = 2r. Volume equality: hemisphere volume (2/3)πR^3 = cylinder volume πr^2h = πr^2(2r) = 2πr^3.
Step-by-Step Solution:
2πr^3 = (2/3)π * 14^3 ⇒ r^3 = (1/3)*14^3 = 2744/3.r = ∛(2744/3) ≈ 9.71 cm (rounded to two decimals).Verification / Alternative check:Then h = 2r ≈ 19.42 cm; check CSA:TSA = 2:3 by substitution holds algebraically.
Why Other Options Are Wrong:10.33, 7.33, 12.33 cm deviate from the exact cube-root result. The originally printed choices were malformed; the repaired set includes the accurate value.
Final Answer:9.71 cm
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