2000 students took a test. The scores were normally distributed with a mean of 70 and a standard deviation of 5.

1. What percentage of grades are between 65 and 80?
2. What percentage of grades are below 60?
3. Approximately, how many students scored more than a 75?
4. Approximately, how many students scored between 65 and 70?
5. If your test grade is 80, what is your Z score?
6. If your test grade is 68, what is your Z score?