A student commutes daily from his home to his university. The average time for a oneway trip is 40 minutes, with a standard deviation of 10 minutes. Assume the distribution of trip times to be normally distributed. What is the probability that a trip will take at least 45 minutes? If the class starts at 8:00 A.M. and the student leaves his house at 7:15 A.M. daily, compute percentage of the time is he late for the class.

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