10.05 Algo (Inferences About the Difference Between Two Population Means: Sigmas Known) Question 2 of 14. Hint(s) Check My Work O USA Today reports that the average expenditure on Valentine's Day was expected to be $100.89. Do male and female consumers differ in the amounts they spend? The average expenditure in a sample survey of 50 male consumers was $136.12, and the average expenditure in a sample survey of 37 female consumers was $68.72. Based on past surveys, the standard deviation for male consumers is assumed to be $31, and the O standard deviation for female consumers is assumed to be $10. The z value is 2.576. Round your answers to 2 decimal places. a. What is the point estimate of the difference between the population mean expenditure for males and the population mean expenditure for females? 5.7014 b. At 99% confidence, what is the margin of error? 11.987 c. Develop a 99% confidence interval for the difference between the twy population means. -2.576 to 2.576 Hide Feedback Incorrect Hint(s) Check My Work