I'm stuck and I need help right now

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.

Which of the following values in the set below will make the equation 5x + 6 = 6 true? (only input the number.) {0, 1, 2, 3, 4}

Aboy who is 1.8 meters tall stands 1 meter away from a lamppost and casts a shadow 2 meters long. the height of the lamppost meters.