[Q7.] For each of the following functions, try to prove that they are continuous at zo. Otherwise, show/say why they are discontinuous. (15pts) z3+1 (a) f(z) = |z| 1 Z 1 20 = -i -1, (b) f(z) = Arg(z/i); zo = i |z| = 1 If All correct, - 1