in the lab, teresa has two solutions that contain alcohol and is mixing them with each other. she uses 4 times as much
solution a as solution b. solution a is 17% alcohol and solution b is 12% alcohol. how many milliliters of solution b does
she use, if the resulting

mixture has 560 milliliters of pure alcohol?
number of milliliters of solution b:

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.