The time needed to complete the final exam for Math 106 is normally distributed with a mean of 75 minutes and a standard deviation of 10 minutes. For each question below, draw, label, and shade the area that you are interested in finding. Answers should have at least 4 decimal places of accuracy.
a. What is the probability of completing the exam in one hour or less?
b. What is the probability that a student will complete the exam in more than 60 minutes but less than 80 minutes?
c. Assume that the examination period is 90 minutes in length. What percentage of the students will not be able to finish within the allotted time?