Each of 154 newly manufactured items is examined and the number of scratches per item is recorded (the items are supposed to be free of scratches), yielding the following data: number of scratches per item 0 1 2 3 4 5 6 7 observed frequency 14 40 43 25 10 15 4 3 let x = the number of scratches on a randomly chosen item, and assume that x has a poisson distribution with parameter μ. (a) find an unbiased estimator of μ and compute the estimate for the data. [hint: e(x) = μ for x poisson, so e(x) = ? ] (round your answer to two decimal places.) 1 (b) what is the standard deviation (standard error) of your estimator? compute the estimated standard error. [hint: σx2 = μ for x poisson.] (round your answer to three decimal places.)