Answer:
4
Step-by-step explanation:
A "board foot" is 1/12 of a cubic foot. It is the volume of a board 1" thick and 1 foot square.
Here, the board is 1" thick, so the number of board feet is numerically equal to the number of square feet of area it has.
(1/2 ft)(8 ft) = 4 ft²
The number of board feet is 4.