Hi I have some graph problems I need help on.

Sketch a graph of velocity vs. time.

A cart is moving to the right on a horizontal surface while a constant net force of 3 newtons acts on it to the left. the force acting on the cart stops after a short period of time. At this time, the cart is still moving to the right.

A cart, starting at rest, is acted upon by a constant force of 3 newtons for 3 seconds at which point the force ceases.

Thank you