50 men took a dip in a water tank 40m long and 20m broad on a religious day. If the average displacement of water by a man is 4 m3, then the rise in the water level in the tank will be-

A 25cm

B 30cm

C 35cm

D 50 cm

Correct Answer: Option A

Total volume of water displaced = (4 x 50) m3 = 200 m3.

Rise in water level = 200/(40*20) m = 0.25 m = 25 cm