Answer:
a) Option C) The score was 2.49 standard deviations higher than the mean score in the class.
b) 2.3%
Step-by-step explanation:
a) We are given that the distribution of test grades is a bell shaped distribution that is a normal distribution.
Formula:
Option C) The score was 2.49 standard deviations higher than the mean score in the class.
b) The z-score for a particular score is -2.
We have to evaluate
P(z < -2)
Calculating the value from normal z-table.
Thus, 2.3% of of the class scored lower than my friend.