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A) a. Determine the sample size required to estimate

a population mean to within 10 units given that the population standard deviation is 50. A confidence level of 90% is judged to be appropriate.

b. Repeat part (a) changing the standard deviation to 100.

c. Re-do part (a) using a 95% confidence level.

d. Repeat part (a) wherein we wish to estimate the population mean to within 20 units.

B) Review Exercise A). Describe what happens to the sample size when

a. the population standard deviation increases.

b. the confidence level increases.

c. the bound on the error of estimation increases.

C) a. A statistics practitioner would like to estimate

a population mean to within 50 units with 99% confidence given that the population standard deviation is 250. What sample size should be used?

b. Re-do part (a) changing the standard deviation to 50.

c. Re-do part (a) using a 95% confidence level.

d. Re-do part (a) wherein we wish to estimate the population mean to within 10 units.

D) Review the results of Exercise C). Describe what happens to the sample size when

a. the population standard deviation decreases.

b. the confidence level decreases.

c. the bound on the error of estimation decreases.