What are the coefficient of 7k-8k

Jonah buys a television that costs $445. sales tax in his state is 7 percent. which of the following expressions represent the amount of tax on the television?

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

Miranda drove her car 112 miles on a 4 gallons of gas and 182 miles on 6.5 gallons. how many gallons would she need to drive 420 miles?