Afreight train rolls along a track with considerable momentum. if it were to roll at the same speed but had twice as much mass, it's momentum would be

The momentum would be doubled

Explanation:

The magnitude of the momentum of the freight train is given by:

where

m is the mass of the train

v is its speed

In this problem, we have that the speed of the train is unchanged, while the mass of the train is doubled:

therefore, the new momentum is

so, the momentum has also doubled.

the right answer is 0.3 meters per second