0 Question 17 v In a lottery, 150 tickets are sold at 1 dollars per ticket. There is 1 first prize of $50.00, 3 second prizes of $30 and 4 third prizes of $10.00. a. Find the net expected winnings {amount won - cost of ticket} on one ticket. Your answer might be positive or negative. Round to two decimals. Keep at least four decimals in any intermediate calculations. The expected net gain is S b. Should you play this lottery? '33:? Yes, since expected net gain is not negative '33 No , since expected net gain is negative . Question 18 v C1\" 5 pts 0 Salaries at a company are normally distributed with a mean of $37000 and standard deviation $2000. Find the following. Round to one decimal if needed. a. The percentile of a salary of 538400: b. The cutoff for the top 12% of salaries: c. Out of a random sample of 84 salaries, how many would you expect to be between 538400 and 539400 : \f0 Question 20 v in the past, trout in Clearwater Creek were 15.8 inches long on average, with a 2.9 inch standard deviation. A recent sample of 34 trout from the creek found a,\" = 13.5. a. Build a 91% CI for the current mean length of trout in Clearwater Creek, using the old standard deviation as a. Round all intermediate calculations to two decimals, then construct the CI and enter like this: (min,max}. Be sure to include the parentheses or you will be marked wrong. Note: if you use a built-in Cl command on a calculatorr'computer, you might get marked wrong due to rounding. Use the formulas given in the textr'notes. b. Use your CI to decide whether the mean length of trout in Clearwater Creek has changed from 15.8 inches. '33:? No, the mean has not changed since the old value of ,u is right in the middle of the new CI 0 Yes, the mean has probably changed since the new Cl does not contain the old value of ,u '33:? No, the mean has probably not changed since the new Cl contains the old value of p '33:? Yes, the mean has probably changed since the old value of ,u is not right in the middle of the new CI