From Newton's second law of motion,
F = ma = mv/t
Where F is force, m is mass, a is acceleration, v is velocity, and t is time. Substituting the known values from the given,
(a) 5 N = (2 kg)(v)/(5 s) ; v = 12.5 m/s
(b) 10 N = (2 kg)(v) /(5 s) ; v = 25 m/s
(c) 15 N = (2 kg)(v) /(5s) ; v = 37.5 m/s
Therefore, the greater the amount of force, the higher is the final velocity of the block.