A national air traffic control system handled an average of 47,208 flights during 29 randomly selected days in a recent year. The standard deviation for this sample is 6,268 flights per day. Complete parts a through c below.       Question content area bottom Part 1 a. Construct a 99​% confidence interval to estimate the average number of flights per day handled by the system.   The 99​% confidence interval to estimate the average number of flights per day handled by the system is from a lower limit of enter your response here to an upper limit of enter your response here. ​(Round to the nearest whole​ numbers.) Part 2 b. Suppose an airline company claimed that the national air traffic control system handles an average of​ 50,000 flights per day. Do the results from this sample validate the airline​ company's claim?     A. Since the 99​% confidence interval does not contain​ 50,000, it can be said with 99​% confidence that the sample validates the airline​ company's claim.   B. Since the 99​% confidence interval contains​ 50,000, it can be said with 99​% confidence that the sample validates the airline​ company's claim.   C. Since the 99​% confidence interval does not contain​ 50,000, it cannot be said with 99​% confidence that the sample validates the airline​ company's claim.   D. Since the 99​% confidence interval contains​ 50,000, it cannot be said with 99​% confidence that the sample validates the airline​ company's claim. Part 3 c. What assumptions need to be made about this​ population?     A. Since the sample size is not greater than or equal to​ 30, one needs to assume that the population follows the​ Student's t-distribution.   B. Since the sample size is not greater than or equal to​ 30, one needs to assume that the population distribution is skewed to one side.   C. Since the sample size is not greater than or equal to​ 30, one needs to assume that the population follows the normal probability distribution.   D. Since the sample size is not greater than or equal to​ 30, one needs to assume that the population distribution is not very skewed to one side.

In a survey, 24 people were asked how much they spent on their child's last birthday gift. The results were roughly bell-shaped with a mean of $36 and standard deviation of $15. Construct a confidence interval at a 90% confidence level.

An emergency planning administrator needs an estimate of the mean weight of relief vehicles when fully loaded. She selects a random sample of 500 trucks and finds a mean of 12.2 tons with a sample standard deviation of 2.9 tons. The width of the 95 percent confidence interval for the population mean is (enter the correct answer rounding to two significant digits (e.g. 3.14)) ?

Suppose a study was conducted of community colleges in California to determine the average cost of tuition for in-state students. The study consisted of 45 community colleges from California. Based on the sample data, the average tuition was $1,440 and the standard deviation was $267. Use this information to construct and interpret a 92% confidence interval for the true average tuition of all California community colleges. Make sure to check any relevant assumptions and state how you determined whether or not they were satisfied (Be as specific as possible). Make sure to type your confidence interval in an interval format with each bound rounded to 3 decimal places [i.e. (12.345, 45.678)]

You measure 33 textbooks' weights, and find they have a mean weight of 62 ounces. Assume the population standard deviation is 4.6 ounces. Based on this, construct a 95% confidence interval for the true population mean textbook weight

The mean length of 25 newly hatched iguanas is 7.47 inches with a standard deviation of 0.77 inches. Assume that the lengths of all newly hatched iguanas are normally distributed.   Step 1 of 2 :  Calculate the margin of error for a 98% confidence interval. Round your answer to two decimal places.

Which type of confidence interval should you use in this situation? A sample of 25 different payroll departments found that the employees worked an average of 310.3 days a year with a standard deviation of 23.8 days. The distribution is approximately normally distributed. Find the 90% confidence interval for the average days worked of all payroll departments.   Question 2 options:   1)  a confidence interval for the mean using a table value from the standard normal distribution.   2)  a confidence interval for the mean using a table value from the t distribution.   3)  a confidence interval for a proportion using a table value from the standard normal distribution.   4)  a confidence interval for proportion using a table value from the t distribution.   5)  none of the above.

You measure 37 textbooks' weights, and find they have a mean weight of 69 ounces. Assume the population standard deviation is 12.9 ounces. Based on this, construct a 80% confidence interval for the true population mean textbook weight.Report your answers to three decimal places.