The scores of students on a college entrance exam were normally distributed with a mean of 19.4 and a standard deviation of 6.3. a. If a sample of 70 students who took the test (who have the same distribution as all scores) is collected, what are the mean and standard deviation of the sample mean for the 70 students? (Answer in 2 decimal places) b. What is the probability that a random sample of 50 students will have an average score of 22 or higher? (Answer in 2 decimal places)