Surface area , is formed by 6 faces,( 4 rectangles, 2 trapezoids )
Frontal face area= 13ft x 15 ft = 195 ft2
Back face area= 10ft x 15ft = 150 ft2
Lateral face 1= 8ft x 15ft = 120 ft2
Lateral face 2= 7ft x 15ft = 105 ft2
Upper face (Trapezoid)= 10ft x 7ft= 70 ft2 AND
. (13-10)ft x 7/2= 21/2= 10.5 ft2
. = 80.5 ft2
Lower face (trapezoid) is also= 70 ft2 + 10.5ft2= 80.5 ft2
NOW sum up all these 6 areas
Then
Surface Area= 195 + 150 +120 + 105 +80.5 + 80.5= 731 ft2
.
