# Two airplanes are flying in the same direction in adjacent parallel corridors.At time t=0,the first airplane is 10 km ahead of the second one.

Two airplanes are flying in the same direction in adjacent parallel corridors.At time t=0,the first airplane is 10 km ahead of the second one.Suppose the speed of the first plane (km/hr)is normally distributed with mean 520 and standard deviation 10 and the second plane's speed is also normally distributed with mean and standard deviation 500and 10,respectively.what is the probability that plane 2 did not catch up to plane one after two hours of flight?