For you need the surface area of the bottom part. all four side are 10*2 in = 20 20*4 = 80 the top and bottom are both 10*10 = 100 100*2 = 200 total = 280 in
The surface area of the top part: top and bottom both 5*5 = 25 25*2 = 50 all four sides are 5*8 = 40 40*4 = 160 total = 210 in
Because the top and bottom part stand on each other, you count the bottom of the top part double. Surface area bottom part = 280 Surface area top part = 210 210+280= 490 So it probably would be 490 in.
