In a simple random sample of 1000 people age 20 and over in a certain country, the proportion with a certain disease was found to be 0.085 (or 8.5%). Complete parts (a) through (d) below. b. Find the margin of error, using a 95% confidence level, for estimating this proportion. m= (Round to three decimal places as needed.) c. Report the 95% confidence interval for the proportion of all people in the country age 20 and over with the disease. The 95% confidence interval for the proportion is (HD. (Round to three decimal places as needed.)

In a study of government financial aid for college​ students, it becomes necessary to estimate the percentage of​ full-time college students who earn a​ bachelor's degree in four years or less. Find the sample size needed to estimate that percentage. Use a 0.04 margin of error and use a confidence level of 95%.Complete parts​ (a) through​ (c) below.   a. Assume that nothing is known about the percentage to be estimated. n=? ​(Round up to the nearest​ integer.)   b. Assume prior studies have shown that about 60​% of​ full-time students earn​ bachelor's degrees in four years or less.   n=? ​(Round up to the nearest​ integer.)   c. Does the added knowledge in part​ (b) have much of an effect on the sample​ size?     A. ​No, using the additional survey information from part​ (b) does not change the sample size.   B. ​Yes, using the additional survey information from part​ (b) dramatically reduces the sample size.   C. ​No, using the additional survey information from…

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A doctor wants to estimate the mean HDL cholesterol of all​ 20- to​ 29-year-old females. How many subjects are needed to estimate the mean HDL cholesterol within 3 points with 99% confidence assuming s=17.8 based on earlier​ studies? Suppose the doctor would be content with 99% confidence. How does the decrease in confidence affect the sample size​ required? a. A​ 99% confidence level requires _______ subject. b. 90% confidence level requires ________ subject. c.How does the decrease in confidence affect the sample size​ required? a.Decreasing the confidence level decreases the sample size needed.   b.Decreasing the confidence level increases the sample size needed.   c.The sample size is the same for all levels of confidence.