Two airplanes are flying in same direction in adjacent parallel corridors. At time t = 0, first airplane is 10 km ahead of second one. Assume the speed of the first plane (km/hr) is normally distributed with mean 530 and standard deviation 9 and the second plane's speed is also normally distributed with mean and standard deviation 515 and 9, respectively.
A) What is the probability that after 2 hr of flying, the second plane has not caught up to the first plane?