To find the total area of the town of Oak Manor, you can use the formula for the area of a rectangle, which is:
\[ \text{Area} = \text{Length} \times \text{Width} \]
Given that the dimensions are 3.8 miles and 4.2 miles, we calculate:
\[ \text{Area} = 3.8 , \text{miles} \times 4.2 , \text{miles} = 15.96 , \text{miles}^2 \]
Therefore, the correct response is:
15.96 mi²