Problem 4. (10 pts.) (z-test) Suppose three radar guns are set up along a stretch of road to catch people driving over the speed limit of 40 miles per hour. Each radar glm is known to have a normal measurement error modeled on N (O, 52). For a passing car, let it be the average of the three readings. Our default assumption for a car is that it is not speeding. a) Describe the above story in the context of N HST. Are the most natural null and alternative hypotheses simple or compound? b) The police would like to set a threshold on it for issuing tickets so that no more that 4% of the tickets are given in error