The distance between consecutive flaws on a roll of sheet aluminum is exponentially distributed with mean distance 3 m. Let X be the distance, in meters, between flaws. a) What is the mean number of...

The distance between consecutive flaws on a roll of sheet aluminum is exponentially distributed with mean distance 3 m. Let X be the distance, in meters, between flaws. a) What is the mean number of flaws per meter? b) What is the probability that a 5 m length of aluminum contains exactly two flaws?