20 if m* (e) = 0, prove that m* (e 2) = 0, where e = {x:x e e}. [hint: first consider the case where e is bounded.] 21. if f : r> r satisfies |f(x) - f(y)| < k]

20 If m* (E) = 0, prove that m* (E 2) = 0, where E = {x:x E E}. [Hint: First consider the case where E is bounded.] 21. If f : R> R satisfies |f(x) - f(y)| < K]x - y | for all x and y, show that mfE)) < Km*(E) for any ECR.