1. Which of the following examples would use the z-distribution: x = 100; u = 99; s = 5; n = 70 x - 50: u - 53: 0 - 7: 0 - 15 x = 7; u = 4; s = 1; n = 20 x - 15: u - 17:0 - 3:n - 45 2. Know how to calculate point est., confidence interval, max tolerable error. Know the effect when you change the confidence level and the sample size. A high school surveyed their graduates on their starting salaries. 300 were returned. The average starting salary of the surveys returned was $32,000 with a standard deviation of $5,000. A. What is the point estimate for the starting salary of the graduates? Hint: One number! B. What is the 95% confidence interval for the average salary of all graduates? Hint: Range C. What is the value of the Maximum Tolerable Error for the above confidence interval?? Hint: This is the number that follows +/- in the confidence interval formula. You add it to and subrtact it from the mean!D. If the level of confidence changes to 99%, and all other variables remain unchanged, what will happen to the confidence interval??? E. If the number of graduates returning the survey changes from 300 to 700, all other variables remaining unchanged, what will be effected??? (Probability of error? Point estimate? Confidence Interval?) Hint: Only one changes! 3. Know how to calculate sample size: A restaurant would like to estimate the average $ amount of a take-out order. The standard deviation is $15. If a 99% confidence level and an interval (error) of $5 is desired, how many customers should be in the sample? Hint: The formula is on the formla sheet in the "Useful Resources" Module. "n