An object of mass 10 kg is moving with an initial velocity of `10 m s^(-1)`. A constant force acts for 4 s on the object giving it a speed of 2 m `s^(-1)` in the opposite direction. Find the acceleration and force.
A. `3m//sec^(2)`
B. `-3m//sec^(2)`
C. `0.3m//sec^(2)`
D. `-0.3m//sec^(2)`
