I need help please don’t scam or no brainlist

The sales totals at macy's food store have increased exponentially over the months. which of these best shows the sales in the first three months?

For what values of the variable x is the expression square root of 7x+14+ square root of 7-x a real number?

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.