The board of examiners that administers the real estate broker's examination in a certain state found that the mean score on the test was 527 and the standard deviation was 72. Assume that the scores are normally distributed. (a) (5 pts) What percentage of applicants score less than 550 on the test? (b) (5 pts) If the board wants to set the passing score so that only the best 80% of all applicants pass, what is the passing score?