You may need to use the appropriate appendix table or technology to answer this question A newspaper reports that the average expenditure on Valentine's Day is $100.89. Do male and female consumers differ in the amounts they spend? The average expenditure in a sample survey of 40 male consumers was $13.67, and the average expenditure in a sample survey of 30 female consumers was $61 64. Based on past surveys, the standard deviation for male consumers is assumed to be $45, and the standard deviation for female consumers is med be $20 (a) What is the point estimate (in delars) of the difference between the population mean expenditure for males and the population mean expenditure for females? (Use male-female) $171.53 (b) At 99% confidence, what is the margin of error on dollars)? (Round your answer to the nearest cent.) $20.00 (1) Develop a 99% confidence interval on dolars) for the afference between the two population means. (Use male-female. Round your answer to the nearest cent)