A problem with a telephone line that prevents a customer fro

A problem with a telephone line that prevents a customer from receiving or making calls is disconcerting to both the customer and the telephone company. These problems can be of two types: those located inside a central office and those located on lines between the central office and the customer\'s equipment. The table at right contains a portion of the data reported to three different offices of a telephone company (note, 20 samples were taken from the first two offices, only 15 samples were taken from the third).Shown is the time (in minutes) to clear these problems from the customers\' lines, the corresponding ranks of each of these times, and some summary statistics. Assuming that the samples are randomly selected from populations with equal variances-but not normally-distributed- is there evidence of a difference in the median waiting time between the three offices? Use the 0.01 level of significance and, to receive full credit, show all of the necessary calculations. There is / is not (circle one) evidence of a difference in the median waiting time between the three offices.

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