Answer
a) False
b) False
c) False
Work Step by Step
a) Moving at constant speed, the engine pulls with a force equal to the force of friction, which is normally much less than the train's weight.
b) As per Newton's third law, the engine's pull on the first car and that car's pull on the engine will be always equal in magnitude and opposite in direction.
c) Its inertia would cause it to keep coasting at a fixed speed. The frictional force would cause the train to slow down and finally stop.