Notes. (i) Prior to doing problems 20 and 25, you should do (or at least attempt) the third problem on the Extra Credit homework, whose results you may assume when doing Rosenlicht's problem. (ii) Problem 22 shows that if a function f is analytic at a, and is not identically zero on an open neighborhood of a, then the zeroes of f cannot cluster at a. (iii) Problem 23 shows that if a function f is analytic at a, with open interval of convergence I, then f is analytic at each point of I. (iv) In problem 24, show the conclusion of the last "hence ..." by considering the derivative of the function log(f).