5.13 IQ scores on the WAIS test approximate a normal curve with a mean of 100 and a standard deviation of 15. What \"21 more is identied with (a) the upper 2 percent, that is, 2 percent to the right [and 98 percent to the left)? (b) the lower 10 percent? (c) the upper 60 percent? [d] the middle 95 percent? [Remember. the middle 95 percent straddles the line perpendicular to the mean [or the 50th percentile}, with half of 95 percent, or 47.5 percent, above this line and the remaining 4?.5 percent below this line.] ie} the middle 99 percent