What is 5 and 1/2 divided by 1/2 step by step ?? It would mean a lot!

If there are 12 moths and some have 31 days and others have 30 days how many have 28 days?

Adriver from the university of florida women’s swimming and diving team is competing in the in ncaa zone b championships

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.