Many homeowners rely on handymen to perform small jobs, such as repairs or maintenance, around their residence. According to HomeAdvisor Inc., the average cost for a handyman project varies substantially between the cities of New York, Chicago, Denver, and Atlanta. To test this claim, a random sample of handyman projects from each city was selected and can be found in the Excel file handyman.xlsx.

a. Using α = 0.01, test to determine if a difference exists in the average cost of handyman projects in these four cities.

b. If appropriate, perform a multiple comparison test to determine which pairs are different using α = 0.01.