Solve the given parts of following problem:
Problem: A transport plane takes off from a level landing field with two gliders in tow, one behind the other. The mass of each glider is 700 kg, and the total resistance (air drag plus friction with the runway) on each may be assumed constant and equal to 2700N. The tension in the towrope between the transport plane and the first glider is not to exceed 12000 N.
Part A: If a speed of 40 m/s is required for takeoff, what minimum length of runway is needed?
Part B: What is the tension in the towrope between the two gliders while they are accelerating for the takeoff?
Please show all work and steps to find what minimum length of runway is needed.