To rewrite \( \log(1/125) \) using the power rule of logarithms, we can start by expressing \( \frac{1}{125} \) in terms of powers of 5.
Since \( 125 = 5^3 \), we can rewrite \( \frac{1}{125} \) as \( \frac{1}{5^3} = 5^{-3} \).
Now, applying the logarithmic property that says \( \log(a^b) = b \log(a) \):
\[ \log(1/125) = \log(5^{-3}) = -3 \log(5). \]
Thus, we find that:
\[ \log(1/125) = -3 \log(5). \]
This matches option 1:
1) -3log(5)
So the correct option is 1).