Part d please In 2017, Americans spent a record-high $9.1 billion on Halloween related purchases (the balance). Sample data showing the amount spent on a Halloween costume are: 12 69 22 64 33 36 31 44 52 16 13 98 45 32 63 26 (a) What is the estimate of the population mean amount adults spend on a Halloween costume? (b) What is the sample stan

77​% of U.S. adults think that political correctness is a problem in America today. You randomly select six U.S. adults and ask them whether they think that political correctness is a problem in America today. The random variable represents the number of U.S. adults who think that political correctness is a problem in America today. Answer the questions below. What is the mean?   What is the variance?   what is the standard deviation?    Interpret the results

DATAfile: Costco You may need to use the appropriate technology to answer this question. Consumer Reports uses a 100-point customer satisfaction score to rate the nation's major chain stores. Assume that from past experience with the satisfaction rating score, a population standard deviation of ? = 13 is expected. In 2012, Costco, with its 432 warehouses in 40 states, was the only chain store to earn an outstanding rating for overall quality. A sample of 15 Costco customer satisfaction scores follows. 95 90 83 75 95 98 80 83 82 93 86 80 94 64 62 (a) What is the sample mean customer satisfaction score for Costco?   (b) What is the sample variance? (Round your answer to two decimal places.)   (c) What is the sample standard deviation? (Round your answer to two decimal places.)   (d) Construct a hypothesis test to determine whether the population standard deviation of ? = 13 should be rejected for Costco. With a 0.05 level of significance, what is your conclusion?…

Question: A company conducted a survey to gather data on the ages of its employees. The collected data are as follows: 25, 28, 30, 35, 38, 40, 42, 45, 48, 50. Calculate the range, variance, and standard deviation of the ages.