B webassignnet A In a study investigating the effect of car speed on accident severity, 5,000 reports of fatal automobile accidents were examined, and the vehicle speed at impact was recorded for each one. For these 5,000 accidents, the average speed was 45 mph and the standard deviation was 14 mph. A histogram revealed that the vehicle speed at impact distribution was approximately normal. (Use the Empirical Rule.) (a) Approximately what percentage of these vehicle speeds were between 31 and 59 mph? approximately % (b) Approximately what percentage of these vehicle speeds exceeded 59 mph? (Round your answer to the nearest whole number.) approximately % Need Help? 2. [I3 Points] PODSTAT6 4.4.049.Ml. ASK YOUR TEACHER PRACTICE ANOTHER A student took two national aptitude tests. The national mean and standard deviation were 425 and 100, respectively, for the rst test, and 40 and 10, respectively, for the second test. The student scored 625 on the rst test and 55 on the second test. Use z-scores to determine on which exam the student performed better relative to the other test takers. ' rst exam ' second exam Need Help? @ @ @ 3. {-13 Points] PODSTAT6 4.4.056. ASK YOUR TEACHER PRACTICE ANOTHER Suppose that the average reading speed of students completing a speed-reading course is 500 words per minute (wpm). If the standard deviation is 70 wpm, find the z score associated with each of the following reading speeds. (Round the answers to two decimal places.) 350 wpm 525 wpm 440 wpm 680 wpm