1. Volume is Length x width x height.
Volume = 6 x 4 x 8 = 192 ft^2
Answer is D.
2. Divide the volume by the height to get the area of the base.
Area of base = 312 / 12 = 26 in^2
Answer is D.
3. A 1/2 x 8 x 6 = 24 x 12 = 288 cm^3
B. (12 +6)/2 x 5 = 45 x 14 = 630 m^3
4. See attached picture.