(a) Write down the advantages of parametric tests over non parametric test (b) A temporary employment agency advertises that its employees are placed in positions where the median income is $500. A random sample of employee records revealed the following weekly earnings. At a=0.05, can the agency's claim be refuted? (Critical value= 4) 510 475 495 500 487 500 500 482 495 490 495 520 480 498 535 475 480 482 A . BI E E S'S