3. (25p.) The mean travel time from city A to city B by car during the night is known to be 180 minutes with a standard deviation 30 minutes. Assume normality to answer the below questions. a. Find the probability that a car leaving city A at 9:00PM arrives city B before the midnight. b. Find the probability that a car leaving city A at 9:00PM arrives city B after 1:00AM. c. Find the probability that the mean time travel time of 4 cars leaving city A at 9PM is less than 3 hours. d. Find the probability that the mean time travel time of 4 cars leaving city A at 9PM is more than 3.5 hours. e. Find the probability that the mean time travel time of 4 cars leaving city A at 9PM is between 2.5 and 3.5 hours