Answer: 2520
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Work Shown:
A = area of front triangle = base*height/2 = 20*21/2 = 210
B = area of back triangle = base*height/2 = 20*21/2 = 210
C = area of left rectangle = base*height = 30*21 = 630
D = area of right rectangle = base*height = 30*29 = 870
E = area of bottom rectangle = base*height = 30*20 = 600
F = total surface area
F = A+B+C+D+E
F = 210+210+630+870+600
F = 2520 is the total surface area
Each area unit is in square feet.