19. A manufacturing company has designed a new test of mechanical aptitude for its machinists. Scores on this test approximate a Normal distribution with a mean of 400 and a standard deviation of 60....

Extracted text: 19. A manufacturing company has designed a new test of mechanical aptitude for its machinists. Scores on this test approximate a Normal distribution with a mean of 400 and a standard deviation of 60. a. Carefully sketch a normal curve for this situation below. Be sure to label the mean and one, two, and three standard deviations on each side of the mean. b. What proportion of machinists score higher than 480 on the mechanical aptitude test? с. What proportion of machinists score between 280 and 520 on the mechanical aptitude test? d. What score would a machinist need in order to be in the top 10% of all machinists who would take this test?