A circular wire with diameter 0.2 meters in one a plane. There is a constant Magnetic field with 10T strength. Find the electromotive force and the direction of the current when

(a) The angle changes from 90 to 60 and the wire shrinks to half it's area in 5 seconds.

(b) B increases to 12T in 20 seconds

(c) Wire rotates with w(omega)=4rad/s

(d) B decreases to 8T and wire expands to twice its original diameter in 6 seconds

Please help, and I'd greatly appreciate steps to follow along. Thank you very much!