A unit rate is a comparison of two different quantities where one of the quantities is 1. In other words, it's a ratio that expresses how much of one quantity corresponds to one unit of another quantity.
From the fractions provided:
- \( \frac{27}{1} \) is a unit rate because it compares 27 of one quantity to 1 of another.
- \( \frac{7}{5} \), \( \frac{3}{4} \), and \( \frac{1}{27} \) do not represent unit rates as they do not have a denominator of 1.
Therefore, \( \frac{27}{1} \) is the unit rate you can use.