Each of 150 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 4 567 Observed frequency 18 37 42 30 13 7 2 1 Let X the number of scratches on a randomly chosen item, and assume that X has a Poisson distribution with parameter m