A decorative window is made up of a rectangle with semicircles on either end. The ratio of A D to A B is 3: 2 and A B=30 inches. What is the ratio of the area of the rectangle to the combined areas of the semicircles?
Answer Choices
A. 2: 3
B. 3: 2
C. 6: \pi
D. 9: \pi
E. 30: \pi