2.4.3 lab: conservation of energy need help on 1 and 2

Suppose you were asked to find the torque about point p due to the normal force n in terms of given quantities. which method of finding the torque would be the easiest to use?

An object starts from rest at point f and speeds up continuously as it moves around an oval. a. choose a point about 1/8 th of the way around the oval from point f, and label it point g. draw a vector to represent the velocity of the object at point g. b. determine the change in velocity vector   between points f and g.

The field between two charged parallel plates is kept constant. if the two plates are brought closer together, the potential difference between the two plates either a) decrease b) does not change c) increase?