One -hour carbon monoxide concentrations in air samples from a large city have an approximately exponential distribution with mean 3.6 ppm (parts per...

One -hour carbon monoxide concentrations in air samples froma large city have an approximately exponential distribution with mean 3.6 ppm(parts per million).(a) Find the probability that the carbon monoxide concentration exceeds 9ppm during a randomly selected one-hour period.(b) A traffic-control strategy reduced the mean to 2.5 ppm. Now find theprobability that the concentration exceeds 9 ppm.