Question

which of the following prefixes/base unit represents the smallest metric unit?
milli
base unit
nano
micro
how many steps apart are the prefixes of milli and nano?
2
3
6
9

Explanation:

Step1: Recall metric - prefix values

Milli represents $10^{- 3}$, base - unit represents $10^{0}$, nano represents $10^{-9}$, micro represents $10^{-6}$. Since $10^{-9}<10^{-6}<10^{-3}<10^{0}$, nano is the smallest.

Step2: Calculate the difference in powers of 10

The power of 10 for milli is - 3 and for nano is - 9. The difference is $|-3-(-9)|=6$.

Answer:

First question: C. Nano
Second question: C. 6