HELP. I'm so confused and the instructor's lesson on this section was so confusing!

The amount of skin covering a person's body (in square feet) depends on the person's height and weight. One model for estimating this skin surface area is:

A(w, h) = 0.6416w^0.425h^0.725 square feet

for a person weighing w pounds who is h feet tall.

If a person 5 feet 5 inches tall who weighs 135 pounds grows 2 inches in height, by approximately how much must this person's weight change if the skin surface area is to remain the same? (Round to two decimal places.)