Best Electronics Inc. offers a “no hassle” returns policy. The number of items returned per day follows the normal distribution. The mean number of customer returns is 10.3 per day and the standard deviation is 2.25 per day.
a. In what percent of the days are there eight or fewer customers returning items?
b. In what percent of the days are between 12 and 14 customers returning items?
c. Is there any chance of a day with no returns?