Find the surface area of the Cube. (Please explain how you do it)

143 in^2

Step-by-step explanation:

This is a rectangular prism, not a cube.  One way in which to find the total surface area is as follows:  find the area of the top, the front and the side, add these together and multiply by 2 (since there are 2 tops, 2 sides, 2 fronts):

Surface area = 2(5*7 + 5*9 + 9*7) in^2 = 2(35 + 45 + 63) in^2 = 143 in^2

because they could drop even lower..