To begin with, you have two walls that are 9x5, or 90 units. Then, you have two 7x5 walls for a total of 70 units, making the total area 160 units. Then, you have two walls that are 18 x 2.5 units, for 90 units. Then, two more walls, at 14x2.5 each, or 70 units. Once again, we have a grand total of 160 units. So, there is no change in the total areas......