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14. A machine produces a part for the automotive industry. 6% of the parts produced were defective in the past, and we believe that the current percentage is not higher. What is the needed sample size for estimating the current percentage of defective parts with the 95% confidence and the 2% margin of error?

a.	310
b.	611
c.	216
d.	542

ANS: D

15. We are interested in conducting a study to determine what percentage of eligible voters will support the incumbent governor in the coming election. Recent polls have indicated that the support changes drastically every week. What is the minimum sample size needed to estimate this percentage with a margin of error of 5% and a 95% confidence?

a.	200
b.	100
c.	58
d.	385

ANS: D