A simple random sample of 60 items from a population with o = 8 resulted in a sample mean of 32. (Round your answers to two decimal places.) (a) Provide a 90% confidence interval for the population mean. to (b) Provide a 95% confidence interval for the population mean. to (c) Provide a 99% confidence interval for the population mean. to

If n = 580 and X = 464, construct a 90% confidence interval for the population proportion, p.Give your answers to three decimals______< p < ______

Abe and Betty want to estimate the mean of a population with known standard deviation o. Abe takes 50 samples whereas Betty takes 80 samples. Which of the following statements are correct? (A) If both Abe and Betty use confidence intervals of the same width, then the confidence level of Abe's interval is smaller than that of Betty's (B) If both Abe and Betty use confidence intervals of the same width, then the confidence level of Abe's interval is larger than of Betty's (C) If Abe and Betty construct confidence intervals with the same confidence level, then the width of Abe's interval is smaller than that of Betty's (D) If Abe and Betty construct confidence intervals with the same confidence level then the width of Abe's interval is larger than that of Betty's (B) and (C). (A) and (D) (B) and (D) (A) and (C)

Professor Nord stated that the mean score on the final exam from all the years he has been teaching is a 79%.  Colby was in his most recent class, and his class’s mean score on the final exam was 82%.  Colby decided to run a hypothesis test to determine if the mean score of his class was significantly greater than the mean score of the population.  α = .01. What is the mean score of the population? What is the mean score of the sample? Is this test one-tailed or two-tailed? Why?