1) Dado os conjuntos A = {1, 4, 6, 9} e B = {1,6,7, 10}, a união de A com B (A ∪ B) é: a) A ∪ B = {1, 4, 6, 7, 9, 10}
b) A ∪ B = {1, 6, 9}
c) A ∪ B = {1, 6}
d) A ∪ B = {6, 9}
e) A ∪ B = {1}

Consider the graph of the exponential function y=3(2)×

Graph the line that represents a proportional relationship between d and t with the property that an increase of 33 units in t corresponds to an increase of 44 units in d. what is the unit rate of change of dd with respect to t? (that is, a change of 11 unit in t will correspond to a change of how many units in d? )

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.