Answer: 216
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Work Shown:
A = area of the triangle on top, aka ceiling
A = 0.5*base*height = 0.5*6*8 = 24
B = area of the triangle on the bottom, aka floor
B = A = 24
C = area of the front rectangular face
C = length*width = 10*7 = 70
D = area of the face in back on the left
D = length*width = 6*7 = 42
E = area of the face in back on the right
E = length*width = 8*7 = 56
Total surface area = A+B+C+D+E = 24+24+70+42+56 = 216 square meters
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Alternative Method:
A = area of the triangle on top, aka ceiling
A = 0.5*base*height = 0.5*6*8 = 24
B = area of the triangle on the bottom, aka floor
B = A = 24
LA = lateral area = wall area
LA = (perimeter of the base)*(height)
LA = (6+8+10)*(7)
LA = 24*7
LA = 168
Total surface area = A+B+LA = 24+24+168 = 216 square meters