3 & 4 please
3. [-/6 Points] DETAILS BBBASICSTAT8 8.1.017.MI. MY NOTES PRACTICE ANOTHER Total plasma volume is important in determining the required plasma component in blood replacement therapy for a person undergoing surgery. Plasma volume is influenced by the overall health and physical activity of an individual. Suppose that a random sample of 42 male firefighters are tested and that they have a plasma volume sample mean of x = 37.5 ml/kg (milliliters plasma per kilogram body weight). Assume that a = 8.00 ml/kg for the distribution of blood plasma. (a) Find a 99% confidence interval for the population mean blood plasma volume in male firefighters. What is the margin of error? (Round your answers to two decimal places.) lower limit upper limit margin of error (b) What conditions are necessary for your calculations? (Select all that apply.) O the distribution of volumes is uniform is unknown the distribution of volumes is normal O is known On is large (c) Interpret your results in the context of this problem. The probability that this interval contains the true average blood plasma volume in male firefighters is 0.01. We are 1% confident that the true average blood plasma volume in male firefighters falls within this interval. We are 99% confident that the true average blood plasma volume in male firefighters falls within this interval. The probability that this interval contains the true average blood plasma volume in male firefighters is 0.99. (d) Find the sample size necessary for a 99% confidence level with maximal margin of error E = 3.00 for the mean plasma volume in male firefighters. (Round up to the nearest whole number.) male firefighters Need Help? Read It Watch It Master It 4. [-/11 Points] DETAILS BBBASICSTAT8 8.1.019.MI. MY NOTES PRACTICE ANOTHER Thirty-two small communities in Connecticut (population near 10,000 each) gave an average of x = 137.5 reported cases of larceny per year. Assume that & is known to be 40.7 cases per year. (a) Find a 90% confidence interval for the population mean annual number of reported larceny cases in such communities. What is the margin of error? (Round your answers to one decimal place.) lower limit upper limit margin of error (b) Find a 95% confidence interval for the population mean annual number of reported larceny cases in such communities. What is the margin of error? (Round your answers to one decimal place.) lower limit upper limit margin of error (c) Find a 99% confidence interval for the population mean annual number of reported larceny cases in such communities. What is the margin of error? (Round your answers to one decimal place.) lower limit upper limit margin of error (d) Compare the margins of error for parts (a) through (c). As the confidence levels increase, do the margins of error increase? O As the confidence level increases, the margin of error increases. O As the confidence level increases, the margin of error decreases. As the confidence level increases, the margin of error remains the same. (e) Compare the lengths of the confidence intervals for parts (a) through (c). As the confidence levels increase, do the confidence intervals increase in length? As the confidence level increases, the confidence interval decreases in length. As the confidence level increases, the confidence interval increases in length. O As the confidence level increases, the confidence interval remains the same length
