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Bill scored a 20.7 on the ACT which has an average score of 21.36 and a standard deviation of 1.99. Mariah scored a 1030 on the SAT which has an average score of 1077.43 and a standard deviation of 74.31. What is the z-score for each person rounded to 2 decimal places? (2 points each) 6. Bill's z-score: 7. Mariah's z-score: 8. Who did better on their respective test? Explain how you know in one complete sentence. (2 points) The scores on the National Assessment of Educational Progress 12th grade mathematics test are normally distributed. The mean of the scores on a recent test was 320 and the standard deviation is 38. Round all probabilities to 4 decimal places. (3 points each) 9. Determine the probability that a randomly selected student who took the test had a score less than 385. 10. Determine the probability that a randomly selected student who took the test had a score more than 282. 11. Determine the probability that a randomly selected student who took the test had a score between 305 and 360. 12. If 22,479 students took the test, how many of them had a score between 305 and 360? (round to the nearest wh number)