A 35 cm high bucket in the form ofn frustum is full of water. Radii of its lower and upper ends are 12 cm and 18 cm, respectively. If water from this bucket is poured in a cylindrical drum, whose base radius is 20 cm, then what will be the height of water (in cm) in the drum?

A

16.25

B

18.25

C

19.95

D

20.50