An object of mass 2 kg moving under the action of a force which varies with time as shown in the figure. Which one of the following statements is correct for the interval from 0 to 20 s ?

The momentum of the object increases by 75 ms - 1 .

The momentum of the object decreases by 75 ms - 1 .

The momentum of the object increases by 125 ms - 1 .

The change in momentum cannot be found as the initial speed is unknown.

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The acceleration produced by a force of $5 N$ acting on a mass of $20 kg$ in $m s^{- 2}$ is:

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