You may need to use the appropriate appendix table or technology to answer this question. A simple random sample of n = 56 cars provided a sample mean fuel efficiency of 23.5 mpg and a sample standard deviation of 4.4 mpg. (Round your answers to one decimal place.) (a) Develop a 90% confidence interval for the population mean. to (b) Develop a 95% confidence interval for the population mean. to (c) Develop a 99% confidence interval for the population mean. to (d) What happens to the margin of error and the confidence interval as the confidence level is increased? O As the confidence level increases, there is a larger margin of error and a more narrow confidence interval. O As the confidence level increases, there is a smaller margin of error and a wider confidence interval. O As the confidence level increases, there is a larger margin of error and a wider confidence interval. O As the confidence level increases, there is a smaller margin of error and a more narrow confidence interval.DATAfile: JobSearch You may need to use the appropriate appendix table or technology to answer this question. Older people often have a hard time finding work. AARP reported on the number of weeks it takes a worker aged 55 plus to nd a job. The data on number of weeks spent searching for a job contained in the le JobSearch are consistent with the AARP ndings. 21 14 51 16 17 14 16 12 4B O 27 17 32 24 12 10 52 21 26 14 13 24 19 28 26 26 10 21 44 36 22 39 17 17 10 19 16 22 5 22 (a) Provide a point estimate of the population mean number of weeks it takes a worker aged 55 plus to nd a job. (b) At 95% condence, what is the margin of error? (Round your answer to four decimal places.) (c) What is the 95% condence interval estimate of the mean? (Round your answers to two decimal places.) (d) Discuss the degree of skewness found in the sample data. What suggestion would you make for a repeat of this study? 0 A histogram of the data shows the distribution is perfectly symmetric. One might suggest collecting a larger sample, at least 50, in the future. 0 A histogram of the data shows some evidence that the distribution may be skewed to the right. One might suggest collecting a smaller sample, at most 15, in the future. 0 A histogram of the data shows the distribution is perfectly symmetric. One might suggest collecting a smaller sample, at most 15, in the future. 0 A histogram of the data shows some evidence that the distribution may be skewed to the right. One might suggest collecting a larger sample, at least 50, in the future. DATAfile: HongKongMeals You may need to use the appropriate appendix table or technology to answer this question. The mean cost of a meal for two in a mid-range restaurant in Gaussia is $47. How do prices for comparable meals in Hong Kong compare? The DATAfile HongKongMeals contains the costs for a sample of 42 recent meals for two in Hong Kong mid-range restaurants. 22.78 33.89 22.77 18.04 23.29 35.28 42.38 36.88 38.55 41.68 25.73 34.19 31.75 25.24 26.32 19.57 36.57 32.97 36.83 30.17 37.29 25.37 24.71 28.79 32.83 43.00 35.23 34.76 33.06 27.73 31.89 38.47 39.42 40.72 43.92 36.51 45.25 33.51 29.17 30.54 26.74 37.93 (a) With 95% confidence, what is the margin of error for the estimated mean cost in dollars for a mid-range meal for two in Hong Kong? (Round your answer to the nearest cent.) $ (b) What is the 95% confidence interval estimate of the population mean cost in dollars for a mid-range meal for two in Hong Kong? (Round your answers to the nearest cent.) $ to $ (c) How do prices for meals for two in mid-range restaurants in Hong Kong compare to prices for comparable meals in Gaussia restaurants? The mean cost for a mid-range meal for two in Gaussia is ---Select--- the 95% confidence interval for comparable meals in Hong Kong. This suggests mean cost of comparable meals in Hong Kong is ---Select--- in Gaussia.You may need to use the appropriate appendix table or technology to answer this question. Annual starting salaries for college graduates with degrees in business administration are generally expected to be between $29,000 and $47,600. A 95% condence interval estimate of the population mean annual starting salary is desired. (Round your answers up to the nearest whole number.) What is the planning value for the population standard deviation? E (a) How large a sample should be taken if the desired margin of error is $500? : (b) How large a sample should be taken if the desired margin of error is $200? E (c) How large a sample should be taken if the desired margin of error is $100? S (d) Would you recommend trying to obtain the $100 margin of error'? 0 No, sampling the number of college graduates required to obtain the $100 margin of error would be viewed as too expensive and too much effort by most researchers. 0 Yes, sampling the number of college graduates required to obtain the $100 margin of error would be viewed as easy to obtain by most researchers