How many board feet are in a 2" x 4" x 8' stud?

To determine the number of board feet in a stud that measures 2 inches by 4 inches by 8 feet, you first need to use the formula for calculating board feet, which is:

[ \text{Board Feet} = \left(\frac{\text{Thickness (inches)} \times \text{Width (inches)} \times \text{Length (feet)}}{12}\right) ]

In this case, the thickness is 2 inches, the width is 4 inches, and the length is 8 feet. Plugging these values into the formula:

1. Multiply the thickness by the width and the length:

[ 2 , \text{inches} \times 4 , \text{inches} \times 8 , \text{feet} = 64 ]

2. Then, divide by 12 to convert into board feet:

[ \frac{64}{12} = 5.333... , \text{bd. ft.} ]

This calculation provides the correct number of board feet in the stud, which is approximately 5.333 board feet. Hence, the correct answer is 5.333 bd.