I have no idea how to do circuits like these. can someone help me? please and thanks :)

Modify the equation fδt=δ (mv) to find the force of friction.

Along the line connecting the two charges, at what distance from the charge q1 is the total electric field from the two charges zero? express your answer in terms of some or all of the variables s, q1, q2 and k =14ï€ïµ0. if your answer is difficult to enter, consider simplifying it, as it can be made relatively simple with some work.

Which of the following are used in an electrochemical cell? a. electrodes b. electrolyte c. terminals d. all of the above