In scientific notation and S.I. prefixes, identify the correct name for the factor 10^-12 used for very small quantities in engineering and physics.

Introduction:
SI prefixes enable concise expression of very large and very small quantities. Mastery of these prefixes is crucial for interpreting measurements, performing conversions, and avoiding calculation errors when switching scales in engineering and science.

Given Data / Assumptions:

• The target power of ten is 10^-12.
• We compare it with common prefixes like mega (10^6) and giga (10^9).

Concept / Approach:

Match the specified power of ten to the correct SI prefix. 10^-12 corresponds to 'pico' (symbol p). Familiar counter-examples: mega (M) is 10^6 and giga (G) is 10^9, both for large magnitudes, not small.

Step-by-Step Solution:

Verification / Alternative check:

Cross-check a few examples: 1 picometre = 10^-12 m; 1 picofarad = 10^-12 F. These reinforce the correct association.

Why Other Options Are Wrong:

• Terra: Misspelt for 'tera' and equals 10^12, not 10^-12.
• Giga: 10^9, a large quantity.
• Mega: 10^6, also large.
• None of these: Incorrect since 'pico' is present.

Common Pitfalls:

• Confusing 'tera' (10^12) with 'pico' (10^-12) due to similar spelling.
• Mixing up signs of exponents when converting between units.

Final Answer:

pico