A Charge Q = -7 $\mu$ C Is Uniformly Distributed on a Thin Plastic Ring

A charge Q = -7.8 $\mu$ C is uniformly distributed on a thin plastic ring.The radius of the ring is 4.3 cm.Calculate the electric potential at the center of the ring.Assume that the electric potential is zero at points infinitely far away from the ring.

A) -3.8 * 10⁷ V
B) 3.8 * 10⁷ V
C) 0 V
D) -1.6 * 10⁶ V
E) 1.6 * 10⁶ V