Anew self-serve frozen yogurt store opened this summer that sells its yogurt at a price based upon the total weight of the yogurt and its toppings in a dish. each member of isabelle’s family weighed their dish and this is what they found. determine if the cost is proportional to the weight. how much is the unit cost? (unit cost = cost per ounce)

weight (ounces) : 12.5 10 5 8
cost ($) : 5 4 2 3.20

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.