Two trolleys of masses m and 3m are connected by a spring. They are compressed and released, they move off in opposite direction and come to rest after covering distances s₁ and s₂ respectively. If the frictional force between trolley and surface is same in both the cases then the ratio of distances s₁ : s₂ is

• A

  1:9

• B

  1:3

• C

  3:1

• D

  9:1