Answer: 416 cubic feet
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Explanation:
The volume of any block is V = L*W*H where L,W,H represents length, width and height respectively. The order of multiplication doesn't matter.
The volume of the block on top is 16*4*4 = 256 cubic feet. The "16" is from the fact we subtract the 20 ft and 4 ft.
The volume of the block underneath is 10*4*4 = 160 cubic feet
Add the two volumes to get the final answer: 256+160 = 416 cubic feet.
We can abbreviate "cubic feet" into "ft^3" without quotes.
