Answer: 416 cubic feet
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Explanation:
The block on top has length, width and height of 4, 4 and 20-4 = 16.
The volume of this block is 4*4*16 = 256 cubic feet.
The volume of the block down below is 160 cubic feet because 10*4*4 = 160.
The total volume is therefore: 256+160 = 416 cubic feet
