You may need to use the appropriate appendix table or technology to answer this question. A survey conducted by the American Automobile Association showed that a family of four spends an average of $215.50 per day while on vacation. Suppose a sample of 54 families of four vacationing at Niagara Falls resulted in a sample mean of $254.45 per day and a sample standard deviation of $74.50. (a) Develop a 95% condence interval estimate of the mean amount spent per day in dollars by a family of four visiting Niagara Falls. (Round your answers to the nearest cent.) $ to$ (b) Based on the confidence interval from part (a), does it appear that the population mean amount spent per day by families visiting Niagara Falls differs from the mean reported by the American Automobile Association? Explain. O Ves. The overall average daily vacation expenditure of $215.50 per day is between the upper and lower limits of the condence interval for the population mean at Niagara Falls. This suggests the population mean at Niagara Falls is less than the overall average. 0 Yes. The lower limit for the confidence interval for the population mean at Niagara Falls is greater than overall average daily vacation expenditure of $215.60 per day. This suggests the population mean at Niagara Falls is greater than the overall average. 0 Yes. The upper limit for the condence interval for the population mean at Niagara Falls is less than overall average daily vacation expenditure of $215.60 per day. This suggests the population mean at Niagara Falls is less than the overall average. 0 No. The lower limit for the condence interval for the population mean at Niagara Falls is greater than overall average daily vacation expenditure of $215.60 per day. This suggests we cannot determine if the population mean at Niagara Falls is greater than the overall average daily vacation expenditure. 0 No. The overall average daily vacation expenditure of $215.50 per day is between the upper and lower limits of the confidence interval for the population mean at Niagara Falls. This suggests we cannot determine if the population mean at Niagara Falls is greater than the overall average daily vacation expenditure. You may need to use the appropriate appendix table or technology to answer this question. A research center has conducted extensive research on social media usage. One finding was that 72% of adults aged 18 to 24 use Snapchat. Another finding was that 48% of those aged 18 to 24 use Twitter. Assume the sample size associated with both findings is 600. (a) Develop a 95% confidence interval for the proportion of adults aged 18 to 24 who use Snapchat. (Round your answers to four decimal places.) to (b) Develop a 99% confidence interval for the proportion of adults aged 18 to 24 who use Twitter. (Round your answers to four decimal places.) to (c) In which case, part (a) or part (b), is the margin of error larger? Explain why. The margin of error is larger in ---Select--- |for two reasons. The sample proportion of adults aged 18 to 24 who use Twitter is ---Select--- than the sample proportion of adults aged 18 to 24 who use Snapchat. Therefore, the standard error of the former is ---Select-- than the standard error of the latter. In addition, Za/2 for a 99% confidence interval is ---Select--- V Za/2 for a 95% confidence interval