Answer:
Triangles
A=bxh
= 21x20
=420cm^2
(There are two triangle faces that's why I didn't divide by 2, it simply cancelled out the division of 2)
Base of shape
A=bxh
=20x22
=440cm^2
Front
A=bxh
=22x29
=638cm^2
Back
A=bxh
=22x21
=462cm^2
Total them
420cm^2 + 440cm^2 + 638cm^2 + 462cm^2 = 1960cm^2
Answer is 1960cm^2
Hope this helps!