Full-time Ph. D students receive an average of $12,837 per year. If the average salaries are normally distributed with a standard deviation of $1500, find these probabilities. a. The student makes...

Full-time Ph. D students receive an average of $12,837 per year. If the
average salaries are normally distributed with a standard deviation of $1500, find
these probabilities.
a. The student makes more than $15,000.
b. The student makes between $13,000 and $14,000.