Needed help in (a), (b), and (c)

The N loops of a solenoid are in a uniform magnetic field B , as shown 7 B R a ) Calculate the induced eif E and current I in the solenoid if B = atbt where a and to are positive constants b ) Show the direction of the induced current along the loops and the resistor. " ) Suppose that the direction' of the B field is reversed . What is the answer for port b ) in this case