Final answer:
The appropriate equation to calculate the normal force given kinetic friction is N = f'k / μk, by rearranging the formula f'k = μk N.
Step-by-step explanation:
The equation that can be used to calculate the normal force on an object when you know the speed of the object, the coefficient of kinetic friction, and the force of kinetic friction on the object is f'k = μk N. Here, f'k is the kinetic frictional force, μk is the coefficient of kinetic friction, and N is the normal force. Given that the kinetic frictional force is 45.0 N, you can rearrange the equation to solve for the normal force, yielding the formula N = f'k / μk.