With individual lines at the checkouts, a store manager finds that the standard deviation for the waiting times on monday mornings is 5.2 minutes. after switching to a single waiting line, he finds that for a random sample of 29 customers, the waiting times have a standard deviation of 4.3 minutes. assume that line waiting times on mondays are normally distributed. use a 0.05 significance level to test whether the standard deviation of the waiting times using a single line differs from 5.2 minutes.

What is the range of the relation in the table below? x y –2 0 –1 2 0 4 1 2 2 0

If sin(x) = 0 and cos(x) = 1, what is tan(x)?

Using pert, adam munson was able to determine that the expected project completion time for the construction of a pleasure yacht is 21 months, and the project variance is 4. a) what is the probability that the project will be completed in 17 months? b) what is the probability that the project will be completed in 20 months? c) what is the probability that the project will be completed in 23 months? d) what is the probability that the project will be completed in 25 months? e) what is the due date that yields a 95% chance of completion?