1.  50 men took a dip in a water tank 40 m long and 20 m 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. 20 cm
B. 25 cm
C. 35 cm
D. 50 cm

Answer: Option B

Explanation:

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

Rise in water level = 200 m 0.25 m 
40 x 20

                                = 25 cm.