The proportion of positive COVID-19 cases in Pakistan in May 2020 based on a sample of 100 patients was 5% with a population standard deviation of 10%. What would be the lower bound of a 95% confidence interval. Assume that in a normal distribution, 95% of the observations are within 2 standard deviations of the mean. OA. 1% В. 3% OC. 6% OD. 7%

The newest model of a car battery from a popular brand is supposed to have a lifetime of  60  months, but the lifetime varies slightly from battery to battery. It is known that the population of all lifetimes (in months) of this model of car battery is approximately normally distributed. You are a product reviewer who wants to estimate the standard deviation for this population with a random sample of  22  car batteries. Follow the steps below to construct a  99%  confidence interval for the population standard deviation of all lifetimes of this model of car battery. (If necessary, consult a list of formulas.) (a)Click on "Take Sample" to see the results from the random sample. Take Sample Number of carbatteries Sample mean Sample standard deviation Sample variance 22 57.16 0.38 0.1444   To find the confidence interval for the population standard deviation, first find the confidence interval for the population variance. Enter…

A researcher collected sample data for 19 middle-aged women. The sample had a mean serum cholesterol level (measured in milligrams per one hundred milliliters) of 190.3, with a standard deviation of 9.5. Assuming that serum cholesterol levels for middle-aged women are normally distributed, find a 95% confidence interval for the mean serum cholesterol level of all women in this age group. Give the lower limit and upper limit of the 95% confidence interval. Carry your intermediate computations to at least three decimal places. Round your answers to one decimal place. (If necessary, consult a list of formulas.) Lower limit= Upper limit=

The newest model of a car battery from a popular brand is supposed to have a lifetime of  60  months, but the lifetime varies slightly from battery to battery. It is known that the population of all lifetimes (in months) of this model of car battery is approximately normally distributed. You are a product reviewer who wants to estimate the standard deviation for this population with a random sample of  22  car batteries. Follow the steps below to construct a  99%  confidence interval for the population standard deviation of all lifetimes of this model of car battery. (If necessary, consult a list of formulas.) (a)Click on "Take Sample" to see the results from the random sample. Take Sample Number of carbatteries Sample mean Sample standard deviation Sample variance           To find the confidence interval for the population standard deviation, first find the confidence interval for the population variance. Enter the values…

A sample of 20 cows is drawn to estimate the mean weight of a large herd of cattle.  If the standard deviation of the sample is 96 kg, what is the margin of error in a 90% confidence interval estimate?

A sample of 120 students yielded a sample mean GPA of 3.35, end a sample standard deviation equal to 0.28. Calculate the 95% confidence interval for the population mean GPA.

A researcher collected sample data for 19 middle-aged women. The sample had a mean serum cholesterol level (measured in milligrams per one hundred milliliters) of 191.5, with a standard deviation of 6.5. Assuming that serum cholesterol levels for middle-aged women are normally distributed, find a 95% confidence interval for the mean serum cholesterol level of all women in this age group. Give the lower limit and upper limit of the 95% confidence interval. Carry your intermediate computations to at least three decimal places. Round your answers to one decimal place.  lower limit ____ Upper Limit ____

A random sample of 32 showed that the mean shoe size for American men is 10.5 with a standard deviation of 1.12. Assuming normality, find the 95% confidence interval for the mean shoe size for American men. A random sample of 32 showed that the mean shoe size for American men is 10.5 with a standard deviation of 1.12. Assuming normality, find the 95% confidence interval for the mean shoe size for American men.  (9.99, 11.01)  (10.112, 10.888)  (10.096, 10.904)  (10.174, 10.826)