The standardized verbal scores of students entering a large university are normally distributed with a 600 and a standard deviation of 80. Find the percent of scores that are:
a. Between 600 and 760
c. Less than 360
e. Between 520 and 840
b. Greater than 680
d. Between 440 and 680
f. Greater than 760

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.