The number of hits per day on the Web site of Professional Tool, Inc., is normally distributed

Question:

The number of hits per day on the Web site of Professional Tool, Inc., is normally distributed with a mean of 700 and a standard deviation of 120.
a. What proportion of days has more than 820 hits per day?
b. What proportion of days has between 730 and 820 hits?
c. Find the number of hits such that only 5% of the days will have the number of hits below this number.