Approximately how many cubic feet of water are needed to fill a circular swimming pool that is 70 feet across and 9 feet deep?  Choose the correct option:
A) 4000
B) 10000
C) 20000
D) 35000
E) 45000
Answer Should be D.   V= \pir^2h= \pi*35^2*9= approximately 35000
<result>D</result>
Approximately how many cubic feet of water are needed to fill a circular swimming pool that is 70 feet across and 9 feet deep?