Answer:
See description below
Step-by-step explanation:
Given
Applied Force = 50N
Expected Appled Force = 350N
Difference = 350N - 50N
Difference = 300N
The frictional force will remain unchanged after the applied force gets to 300N.
At this point, the reason why the Net force is not zero (0) is because of the amount of force that is applied.
Also, since the frictional force is less than the applied force, the body will move in the right direction before it gets to 300 N the force of friction equals the applied force.