Let the continuous random variable X denote the distance in micrometers from the start of a track on a magnetic disk until the first flaw. Historical data show that the distribution of X can be modeled by a pdf: f (x) =. 500 500 , X > 0 Find the CDF. OF(x) = 1 - e-300 OF(x) = e-500x OF(x) = e- 300 OF ( x) = ex