Can you please help with the question below.

For a 4-units class like Statistics, students should spend average of 12 hours per week studying for the class. A survey was done on students, and the distribution of total study hours per week is bell-shaped with a mean of 15 hours and a standard deviation of 2 hours. Use the Empirical Rule to answer the following questions. a) 99.7% of the students spend between and hours on this class. b) What percentage of the students between 13 and 21 hours on this class? % c) What percentage of the students below 19 hours? %