The Edison Electric Institute has published figures on the number of kilowatt hours used annually by various home appliances. It is claimed that a vacuum cleaner uses an average of 42 kilowatt hours per year. If a random sample of 15 homes included in a planned study indicates that vacuum cleaners use an average of 45 kilowatt hours per year with a standard deviation of 12 kilowatt hours, does this suggest at the 0.05 level of significance that vacuum cleaners use, on average, greater than 42 kilowatt hours annually? Assume the population of kilowatt hours to be normal