A boat having a length 3 m and breadth 3 m is floating on a lake. The boat sinks by 1 cm when a man gets on it. The mass of the man is:
Answers.
A) 100 kg  B) 120 kg  C) 89 kg  D) 90 kg  E) 110 kg

Rationale: "volume of water displaced = ( 3 x 3 x 0.01 ) m 3 = 0.09 m 3 . mass of man = volume of water displaced x density of water = ( 0.09 x 1000 ) kg = 90 kg . answer : d"
Answer: D