Separate random samples were collected by a polling agency to investigate the difference in employee satisfaction at non-profit organizations and at for-profit companies. Data collected from 454 employees at non-profit

organizations revealed that 407 of them were "highly satisfied." From the for-profit companies, 447 out of 529 employees reported the of satisfied employees are the same at for-profit companies as at non-profit companies. Complete parts a through c below. a) What is the difference in the proportions of the two types of companies? Assume p, is the proportion of satisfiednon-profit employees and p2 is the proportion of satisfied for-profit employees. b) What is the value of the z-statistic?