Answer:
So, what you want to do first is add the height together.
5+5+5+5= 5*4=20
Then use the formula for finding the surface area of a rectangular prism.
A = 2wl + 2lh + 2hw, where w is the width, the l is the length, and the h is the height.
In other words A= 2(12*10) + 2(10*20) + 2(20*12)
Simplify from there.
A= 2(120) + 2(200) + 2(240)
A= 240 + 400 + 480
A= 1,220
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