Ms. James bought 3 world maps for her classroom. The total cost of the 3 maps was $73.77. The clerk told Ms. James that each map cost $2.45. Do you agree with the clerks calculations? Explain your reasoning. please help ASAP please will give branlyist if i can figure it out

A. find the power of the test, when the null hypothesis assumes a population mean of mu = 450, with a population standard deviation of 156, the sample size is 5 and the true mean is 638.47 with confidence intervals of 95 b. find the power of the test, when the null hypothesis assumes a population mean of mu = 644, with a population standard deviation of 174, the sample size is 3 and the true mean is 744.04 with confidence intervals of 95% c. find the power of the test, when the null hypothesis assumes a population mean of mu = 510, with a population standard deviation of 126, the sample size is 10 and the true mean is 529.44 with confidence intervals of 95