Electronic ticketing allows passengers not to worry about a paper ticket, and it costs the airline companies less to handle than paper ticketing. However, in recent times the airlines have received complaints from passengers regarding their e-tickets. To investigate the problem, an independent watchdog agency contacted arandom sample of 20 airportsand collected information on the number of complaints the airport had with e-tickets for the month of March. The information is reported below.

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What assumptionabout the distributionis necessary before conducting a hypothesis test?

Plot the number of complaints per airport using a dotplot. Is it reasonable to conclude that the population follows a normal distribution?