The problem asks to find the height of a parallelogram given its area and base. The area of the parallelogram is 40 $in^2$, and the base is 12 inches.

1. Problem Description

The problem asks to find the height of a parallelogram given its area and base.

The area of the parallelogram is 40 $in^2$, and the base is 12 inches.

2. Solution Steps

The area of a parallelogram is given by the formula:

$Area = base \times height$

We are given the area and the base, so we can solve for the height.

$40 = 12 \times height$

To find the height, we divide the area by the base:

$height = \frac{Area}{base}$

$height = \frac{40}{12}$

Simplify the fraction:

$height = \frac{10}{3}$

Convert the improper fraction to a mixed number:

$height = 3\frac{1}{3}$ inches

3. Final Answer

The height of the parallelogram is $3\frac{1}{3}$ inches.

So the answer is D. $3\frac{1}{3}$ inches.