Independent random samples taken at two companies provided the following information regarding annual salaries of the employees. The population standard deviations are also given below. Company A Company B Sample Size 72 50 Sample Mean (in $1000) 48 43 Population Standard Deviation (in $1000) 12 10 a. We want to determine whether or not there is a significant difference between the average salaries of the employees at the two companies. Compute the test statistic. b. Compute the p-value; and at a=.05, test the hypotheses. c. Which company, if either, appears to have the higher salary? Provide a 95% confidence interval for the difference between the population mean salary of employees for the two companies.