If a length of a rectangle is four times its width. what is its perimeter is 90m. how can i find the dimentions

Karen will divide her garden into equal parts. she will plant corn in 8/12 of the garden. what is the lowest number of parts she can divide her garden into?

Precalculus question, image attached.

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