The article "Gas Cooking, Kitchen Ventilation, and Exposure to Com- bustion Products" reported that for a sample of 50 kitchens with gas cooking appliances monitored during a one-week period, the sample mean CO₂ level (ppm) was 654.16, and the sample standard deviation was 164.43. (a) Calculate and interpret a 95% confidence interval for true average CO₂ level in the population of all homes from which the sample was selected. (b) Suppose the investigators had made a rough guess of 175 for the value of s before collecting data. What sample size would be necessary to obtain an interval width of 50 ppm for a confidence level of 95%?

In a test of the effectiveness of garlic for lowering​ cholesterol, 48 subjects were treated with garlic in a processed tablet form. Cholesterol levels were measured before and after the treatment. The changes ​(before−​after) in their levels of LDL cholesterol​ (in mg/dL) have a mean of 4.1 and a standard deviation of 16.5. Construct a 99​% confidence interval estimate of the mean net change in LDL cholesterol after the garlic treatment. What does the confidence interval suggest about the effectiveness of garlic in reducing LDL​ cholesterol?   Click here to view a t distribution table. LOADING...

In a test of the effectiveness of garlic for lowering​ cholesterol, 48 subjects were treated with garlic in a processed tablet form. Cholesterol levels were measured before and after the treatment. The changes ​(before−​after) in their levels of LDL cholesterol​ (in mg/dL) have a mean of 5.3 and a standard deviation of 17.4. Construct a 90​% confidence interval estimate of the mean net change in LDL cholesterol after the garlic treatment. What does the confidence interval suggest about the effectiveness of garlic in reducing LDL​ cholesterol?   .       What is the confidence interval estimate of the population mean μ​?   enter your response here ​mg/dL<μ<enter your response here ​mg/dL ​(Round to two decimal places as​ needed.)

In a test of the effectiveness of garlic for lowering​ cholesterol, 49 subjects were treated with garlic in a processed tablet form. Cholesterol levels were measured before and after the treatment. The changes ​(before−​after) in their levels of LDL cholesterol​ (in mg/dL) have a mean of 3.2 and a standard deviation of 19.3. Construct a 90​% confidence interval estimate of the mean net change in LDL cholesterol after the garlic treatment. What does the confidence interval suggest about the effectiveness of garlic in reducing LDL​ cholesterol?   What is the confidence interval estimate of the population mean μ​? ___​mg/dL<μ<____​mg/dL ​(Round to two decimal places as​ needed

In a test of the effectiveness of garlic for lowering cholesterol, 47 subjects were treated with garlic in a processed tablet form. Cholesterol levels were measured before and after the treatment. The changes (before - after) in their levels of LDL cholesterol (in mg/dL) have a mean of 3.7 and a standard deviation of 18.2. Construct a 90% confidence interval estimate of the mean net change in LDL cholesterol after the garlic treatment. What does the confidence interval suggest about the effectiveness of garlic in reducing LDL cholesterol? Click here to view a t distribution table. Click here to view page 1 of the standard normal distribution table. Click here to view page 2 of the standard normal distribution table. What is the confidence interval estimate of the population mean p? Question Viewer mg/dL < p< mg/dL (Round to two decimal places as needed.) What does the confidence interval suggest about the effectiveness of the treatment? O A. The confidence interval limits do not…

In a test of the effectiveness of garlic for lowering​ cholesterol, 45 subjects were treated with garlic in a processed tablet form. Cholesterol levels were measured before and after the treatment. The changes (before−​after)in their levels of LDL cholesterol​ (in mg/dL) have a mean of 4.6 and a standard deviation of 16.3. Construct a 95​% confidence interval estimate of the mean net change in LDL cholesterol after the garlic treatment. What does the confidence interval suggest about the effectiveness of garlic in reducing LDL​ cholesterol?     What is the confidence interval estimate of the population mean μ​? ______ mg/dL<μ<_____ ​mg/dL (Round to two decimal places as​ needed.)       What does the confidence interval suggest about the effectiveness of the​ treatment? A. The confidence interval limits contain ​0, suggesting that the garlic treatment did not affect the LDL cholesterol levels. B. The confidence interval limits contain 0, suggesting that the garlic treatment…

In a test of the effectiveness of garlic for lowering cholesterol, 49 subjects were treated with garlic in a processed tablet form. Cholesterol levels were measured before and after the treatment. The changes (before- after) in their levels of LDL cholesterol (in mg/dL) have a mean of 3.1 and a standard deviation of 15.8. Construct a 95% confidence interval estimate of the mean net change in LDL cholesterol after the garlic treatment. What does the confidence interval suggest about the effectiveness of garlic in reducing LDL cholesterol? Click here to view a t distribution table. Click here to view page 1 of the standard normal distribution table. Click here to view page 2 of the standard normal distribution table. What is the confidence interval estimate of the population mean µ? mg/dL mg/dL<µ< (Round to two decimal places as needed.) What does the confidence interval suggest about the effectiveness of the treatment? O A. The confidence interval limits contain 0, suggesting that the…