At time = 0, 20 identical components are tested. The life- time distribution of each is exponential with parameter A. The experimenter then leaves the test facility unmonitored. On his return 24 hours later, the experimenter immediately terminates the test after noticing that y = 15 of the 20 com- ponents are still in operation (so 5 have failed). Derive the mle of A. [Hint: Let Y = the number that survive 24 hours. Then Y-Bin(n, p). What is the mle of p? Now notice that p = P(X,24), where X, is exponentially distributed. This relates A to p, so the former can be estimated once the latter has been.]