1) Find the indicated value of standard normal variable Z, z.02.

Select one:

a.0.02

b.-0.02

c.-2.06

d.2.06

e.2.05

A restaurant owner wishes to estimate, to within 55 seconds, the mean time taken to serve food to customers with 99% confidence. In the past, the standard deviation of serving time has been about 2.5 minutes. Estimate the minimum size of the sample required.

Select one:

a.40

b.41

c.48

d.49

e.50

The heights of male high school students are measured. The average height is found to be 68 inches with a standard deviation of 2 inches. The distribution is approximately normal. If we draw a random sample of 16 boys from the school, then the standard deviation of the sample mean is:

Select one:

a.70

b.0.5

c.1

d.0.25

e.2.5

Find the sample mean.

Select one:

a.143.26

b.130.32

c.131.29

d.142.87

e.135.16