Answer
$\frac{1}{4} \ \text{mi} ^2$.
Work Step by Step
The area is computed by $A = a \cdot b$.
Here, we substitute $a = \frac{3}{4}$ and $b=\frac{1}{3} $. From this it follows that the area $A$ is computed by:
$A = a \cdot b = \frac{3}{4} \cdot \frac{1}{3} = \frac{1}{4} \cdot \frac{1}{1} = \frac{1}{4}$.
With considering the unit, the answer is $\frac{1}{4} \ \text{mi} ^2$.
