The mean of a normal probability distribution is 60; the standard deviation is 5. Refer to the table in Appendix A.1. (Round your answers to 2 decimal place. Omit the % sign in your response.)
a. About what percent of the observations lie between 55 and 65?
Percentage of observations %
b. About what percent of the observations lie between 50 and 70?
Percentage of observations %
c. About what percent of the observations lie between 45 and 75?
Percentage of observations %