#4 (*Use this setting for the subquestions 4-1, 4-2, 4-3, and 4-4 that follow.) Bimble as an expert engineer has taken a leading role in remodeling her company's car engines. She now needs to report the new engine's fuel efficiency for the company's advertisement purposes, but the true mean and standard deviation values are unknown after the remodeling. She took a simple random sample of 30 engines from the production line and recorded the observed fuel efficiency (MPG, miles per gallon) for each of the engines in the sample. Data are found in this Excel file: Exam1 #4.xlsx . (*Click the "" arrow to download the Excel file) Question 6 9 pts 4-1 Bimble runs into the company's CEO and needs to make a quick report of the new engine's performance. What will be Bimble's point estimation of the population mean fuel efficiency (mpg) for this new engine? (to 2 decimals) Report the mpg value with the specified rounding in the box below. Question 7 4-2 Now it seems Bimble has more time and wants to be more confident in her estimation to report to the CEO. To help Bimble, please construct the 95% confidence interval for the population mean of the engine's fuel efficiency. What is the lower limit of the 95% confidence interval? (to 2 decimals) Report the mpg value with the specified rounding in the box below. 9 pts Question 6 9 pts 4-1 Bimble runs into the company's CEO and needs to make a quick report of the new engine's performance. What will be Bimble's point estimation of the population mean fuel efficiency (mpg) for this new engine? (to 2 decimals) Report the mpg value with the specified rounding in the box below. Question 7 4-2 Now it seems Bimble has more time and wants to be more confident in her estimation to report to the CEO. To help Bimble, please construct the 95% confidence interval for the population mean of the engine's fuel efficiency. What is the lower limit of the 95% confidence interval? (to 2 decimals) Report the mpg value with the specified rounding in the box below. 9 pts Question 8 4-3 What is the upper limit of the 95% confidence interval? (to 2 decimals) Report the mpg value with the specified rounding in the box below. Question 9 9 pts 9 pts 4-4 The CEO seems confused as to what the 95% confidence level is about and asked: So, you mean, 95% of the newly produced engines would run between the two numbers you reported above?" Select your best response to the CEO for clarification, assuming that the CEO does not know so much about statistics but does care about accuracy. Yes, I am certain that 95% of the newly produced engines will have mpg values within this range. Not quite, it reports that 95% of the 30 sampled engines had mpg values within this range. No, it means I am 95% certain that the true average mpg value out of all new engines is somewhere within this range. No, the average mpg value of our new engines is right in the middle of the two numbers, but to be 95% certain, I need to stretch my estimation to these two numbers. MPG (miles per gallon) 62.4 50.4 48.4 53.3 57.1 53.6 49.8 59.4 60.4 58.4 53.6 48.0 54.9 45.7 62.9 50.8 60.3 57.4 54.6 46.2 51.5 55.1 52.9 61.7 45.7 53.1 51.4 49.8 50.9 65.5