Asection of books is marked down by 15 percent from an original price of $16 each. how much will it cost to buy three books from the sale section?

The product of two negative rational numbers is always zero sometimes zero never zero

Find and simplify an expression for the area of five rows of x squares with side lengths of x centimeters.

An automobile assembly line operation has a scheduled mean completion time, μ, of 12 minutes. the standard deviation of completion times is 1.6 minutes. it is claimed that, under new management, the mean completion time has decreased. to test this claim, a random sample of 33 completion times under new management was taken. the sample had a mean of 11.2 minutes. assume that the population is normally distributed. can we support, at the 0.05 level of significance, the claim that the mean completion time has decreased under new management? assume that the standard deviation of completion times has not changed.