PLS HELP ASAP I need help on Part: b and c that’s all pls help or I’m in trouble I will pay a lot of points for help

Part B:
AB = 3in
BC = 5in
CD = 7.2in

Part C:
The surface area is 91.2in^2. (91.2 inches squared)
Show your work;
[4 (7.2)]2= 57.6 (both top and bottom rectangles)
3 (7.2)= 21.6 (back rectangle)
4 (3)= 12 (both triangles)
57.6 + 21.6 + 12 = 91.2in^2