An open box is to be made from a flat square piece of material 19 inches in length and width by cutting equal squares of length x from the corners and folding up the sides. (a) write the volume v of the box as a function of x. leave it as a product of factors; you do not have to multiply out the factors.

Arandom sample of 45 observations results in a sample mean of 68. the population standard deviation is known to be 23 a. compute the margin of error at a 959% confidence interval. b. compute the 95% confidence interval for the population mean c. compute the 90% confidence interval for the population mean. d. compute the 75% confidence interval for the population mean