Answer:
1960 cm^2
Step-by-step explanation:
Surface area:
Area of cross section x 2 = 1/2 x 20 x 21 x 2 = 420 cm^2
Area of slope = 29 x 22 = 638cm^2
Area of base = 22 x 20 = 440cm^2
Area of back = 21 x 22 = 462cm^2
Total Surface area = 462+440+638+420 = 1960cm^2
Hope this helps
