Gary is cleaning windows. He sets his ladder 25 feet away from the wall of the house to reach the windows on the second story, which are at a height of 20 feet above the ground. He moves his ladder 15 feet closer to the wall to reach the windows on the third story of the house. Approximately how high above the ground are the windows on the third story of the house?

A.33.5ft
B.28.3ft
C.30.4ft
D.32.0ft