9514 1404 393
Answer:
13,280 cm²
Explanation:
The formula for the area of a cuboid can be written as ...
A = 2(LW +H(L +W))
When the area of the missing top is subtracted, this becomes ...
A = LW +2H(L +W)
Then the area of 10 boxes will be ...
A = 10×(20×16 +2×14(20+16)) = 10(320 +28(36)) = 13,280 cm²