Nylon bars were tested for brittleness. Each of 280 bars was molded under similar conditions and was tested by placing a fixed stress at specified locations on the bar. Assuming that each bar has uniform composition, the number of breaks on a given bar should be Poisson distributed with an unknown a rate of breaks, l, appearing per square inch of bar. The following table summarizes the number of breaks found on the 280 bars:

a. Use a goodness- of- fit test to assess whether the data appear to be from a Poisson model.
b. What is the population of interest in this study?

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Breaks/bar 013 4 5 Total Frequency 12 110 38 7 3 1 280