The average annual income for Australian childcareworkers five years agowas $38100. It is believed this average annual income has essentially remained the same since then. To test this hypothesis, a random sample of 22 Australian childcare workers is selected and the average annual salary is found to be $40200. Taking the population standard deviation for annual income to be $2500 per year, using α = 0.01 and assuming that annual incomes of the workers are normally distributed, test the researcher’s hypothesis.