Answer:
Explanation:
I hate these kinds of problems, luckily I can't understand how much the kinetic friction is for this , the words are all mixed around. and don't read well. Maybe this went through a translator program? My suggestion draw the free body diagram. so you can see where the forces are, and how they are acting. getting the free body diagram right.. usually makes these problems pretty straight forward. just do the steps and you get the answer.
Net force is basically the force an object has when changing direction, so the answer would be D.
The volume dial is acting as a voltage divider or a variable resistor.
