[Faraway Exercise 8.1]. Data are generated from an exponential distribution with density f(y) = exp(y) where , y > 0 (a) Identify the specific form of , , a(), b() and c() for the exponential distribution. (b) What is the canonical link and variance function for a GLM with a response following the exponential distribution? (c) Identify a practical difficulty that may arise when using the canonical link in this instance. (d) When comparing nested models in this case, should an F or 2 test be used? Explain. (e) Express the deviance in this case in terms of the responses yi and the fitted values bi