Verified answer

F = ma. Use that to find the acceleration, which is the change in velocity each second.

So if you have an acceleration of x m/sec^2, the velocity changes by x m/sec every second. Starting at 0, it would be x m/sec after 1 second.

Second question makes no sense. Since F = ma, then the same force is always going to cause a different acceleration on the 5 kg mass than the 1 kg mass.