A. What is the coefficient of kinetic friction?

Explanation:

Coefficient of kinetic friction is the resistive force that opposes the motion of a body as it moves and is in contact with another body.

It is found by dividing the frictional force by the normal force.

Friction is a force that opposes motion. Static friction is for bodies that are not in motion Kinetic friction is for moving bodies.

I'm having some difficulty seeing the diagram clearly.but the question says there's a net inward force on the object.so we know right away,  from newton's 2nd law of motion, thatthat baby is accelerating.  it doesn't even matter which way thenet force is pointing.  if there's any net force, then either theobject's speed or else its direction must be changing.