On a large baking tray, 40 cookies can be baked together. To bake 40 cookies it takes 14 minutes, for baking 80 cookies it takes 28 minutes, for baking 100 cookies it takes 42 minutes. How much time will it take to bake 140 cookies? A. 49
B. 56
C. 57
D. 48

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.

Is triangle jkl congruent to triangle rst? if so, what is the scale factor?

Which expression is equivalent to 64 - 9x^2?