A submarine descends 45 1/2 feet from the ocean surface , climbs 30 feet ,and then descends an additional 18 3/4 feet. What must the submarine do now to reach the ocean surface?
A. Descends 94 1/4 feet
B. Climb 94 1/4 feet
C Descends 34 1/4 feet
D.Climbs 34 1/4 feet