In order to estimate how long it will take to produce a particular product, a manufacturer will study the relationship between production time per unit and the number of units that have been produced. The line or curve characterizing this relationship is called a learning curve (Adler and Clark, Management Science, Mar. 1991). Twenty-five employees, all of whom were performing the same production task for the tenth time, were observed. Each person's task completion _, time (in minutes) was recorded. The same 25 employees were observed again the 30th time they performed the same task and the 50th time they performed the task.The resulting completion timcs are shown in the table below.

a. Use a statistical software package to construct a frequency histogram for each of the three data sets.

b. Compare the histograms. Does it appear that the relationship between task completion time and the number of times the task is perforrncd is in agreement with the observations noted above about production processes in general? Explain.