A) To find the surface area of a cube, you have to use the formula 6•a^2
meaning you just have to calculate one side and multiply it by six.
541.5 is the surface area of the cube.
B) To find the surface area for just five sides, you'll be doing the same, except instead of 6 it'll be five.
so multiply 9.5 by itself
you get 90.25
Then you multiply 90.5 by 5
You get 451.25
Unfortunately I'm not sure how to do C. good luck