5. Suppose your statistics professor reports test grades as zscores, and you got a score Of 2.20 on an exam. Write a sentence explaining what that means. Select the correct choice below. O A. The score was 2.20 points lower than the mean score in the class. Q B. The score was 2.20 points higher than the mean score in the class. Q C. The score was 2.20 standard deviations higher than the mean score in the class. O D. The score was 2.20 standard deviations lowerthan the mean score in the class. 7. An incoming MBA student took placement exams in economics and mathematics. In economics, she scored 34 and in math 85. The overall results on the economics exam had a mean of 75 and a standard deviation of 7, while the mean math score was 70, with a standard deviation of 12. On which exam did she do better compared with the other students? Since she scored standard deviations (1) the mean in economics and standard deviations (2) the mean in mathematics, she did better on the (3) exam. (Round to two decimal places as needed.) (1) O below (2) 0 above (3) O economics 0 above 0 below 0 mathematics B. A forester measured 40 of the trees in a large woods that is up for sale. He found a mean diameter of 10.6 inches and a standard deviation of 4.5 inches. Suppose that these trees provide an accurate description of the whole forest and that a Normal model applies. a) Choose the correct Normal model for tree diameters. OA- 0 B. -2916 81 196151198 24,1 16 61 1nd 151 198 241 23.5 b) What size would you expect the central 95% of all tree diameters to be? Using the 63-95-99] rule, the central 95% of the tree diameters are between inches and inches. (Do not round. Type integers or decimals.) c) About what percent of the trees should have diameters below 1.6 inches? Using the 68-9599] rule, about % of the trees should have diameters below 1.6 inches. (Do not round. Type an integer or a decimal.) d) About what percent of the trees should have diameters between 15.1 and 19.6 inches? Using the 68-9599] rule, about % of the trees should have diameters between 15.1 and 19.6 inches. (Do not round. Type an integer or a decimal.) e) About what percent of the trees should have diameters over 24.1 inches? Using the 63-95991 rule, about "/1: of the trees should have diameters over 24.1 inches. (Do not round. Type an integer or a decimal.)