Answer: 400
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Work Shown:
A = area of parallelogram
A = base*height
A = 20*16
A = 320
B = area of triangle at the very top
B = (1/2)*base*height
B = (1/2)*20*8 ... note: opposite sides of parallelogram are equal
B = 80
C = total area of entire figure
C = A+B
C = 320+80
C = 400
