Thirty cubes are stacked in square layer to form a tower. The bottom layer

 measures 4 cubes by 4 cubes , the next layer 3 cubes by three cubes, the next layer

 2 cubes by 2 cubes and top layer is single cube.

a) Determine the total surface area of the towers of cubes (do not include the bottom ).

 

b) what would be the volume if the bottom layer of cubes was 8 cubes by 8 cubes.