A wheel of a child's bicycle has a circumference that is 50% of the circumference of a child's mountain bicycle wheel. The child's bicycle wheel has a circumference of 37.7 inches. a. What is the radius (to the nearest inch) of the child's bicycle wheel? of the child's mountain bicycle wheel? b. The child's mountain bicycle wheel takes 2 seconds to make 3 revolutions. How fast (to the nearest inch per second) is the bicycle moving?