3. A student daily takes a trip from his suburban home to his midtown school. The trip time is assumed be normally distributed with a mean of 50 minutes and a standard deviation of 10 minutes. a. What is probability that a trip will take at least 1 hour? (7 points) b. If the first class begins at 9:20 A.M. and the student leaves his house at 8:40 A.M., what is probability that he is late for this class? (8 points) c. Find the probability that 3 of the next 4 trips will take at least 1 hour (Trips are independent of one another). (10 points)