a) Show that Green's Theorem does not hold if continuity of P, Q is relaxed at one

Question:

a) Show that Green's Theorem does not hold if continuity of P, Q is relaxed at one point in E. [Consider P = y/(x2 + y2), Q = -x/(x2 + y2), and E = B1(0, 0).]
b) Show that the Divergence Theorem does not hold if continuity of F is relaxed at one point in E.