Answer:
Part a)

Part b)
Since the radius is decreasing so induced current will increase the flux through the coil
So it would be clockwise in direction
Explanation:
As we know that magnetic flux linked with the coil is given as

now the rate of change in flux is given as

now we know that circumference is decreasing at rate of 15 cm/s
so here we know the length of circumference as

So rate of change in circumference is


final length of circumference at t = 8 s

Part a)
Now the induced EMF is given as



Part b)
Since the radius is decreasing so induced current will increase the flux through the coil
So it would be clockwise in direction
It’s ultrasonic 100% not much help but I knew the answer