Which metric prefix indicates a quantity of one trillion atoms?

• A. tera-
• B. giga-
• C. mega-
• D. nano-

Answer: (A)

Verified step by step guidance

1. Understand that metric prefixes are used to denote powers of ten, which help express very large or very small quantities in a compact form.
2. Recall the common metric prefixes and their corresponding powers of ten: mega- (10^6), giga- (10^9), tera- (10^{12}), and nano- (10^{-9}).
3. Identify that one trillion corresponds to 10^{12} atoms, which matches the power of ten associated with the prefix tera-.
4. Compare the given options to their powers of ten to confirm that tera- is the correct prefix for one trillion atoms.
5. Conclude that the metric prefix indicating a quantity of one trillion atoms is tera-.