Answer
$42.7\ ft^3$
Work Step by Step
To find the volume, find the product of the length, width and depth. Use conversion factors to express all the dimensions in feet rather than a mix of feet and inches.
$16\ in\times\frac{1\ ft}{12\ in}\times4\ ft\times8\ ft=42.\underset\uparrow666\overline6\ ft^3$
Since the digit to the right of the tenths digit is greater than 5, round up.