In a study of annual salaries of employees, random samples were selected from two companies to test if there is a difference in average salaries. for company "x", the sample was size 65, the sample mean was $47,000 and the population standard deviation is assumed to be $11,000. for company "y", the sample size was 55, the sample mean was $44,000 and the population standard deviation is assumed to be $10,000. test for a difference in average salaries at a 5% level of significance. what is your conclusion?