Answer
The glider exerts a force of 850 N on the towline and the force is directed to the west.
Work Step by Step
Since the car is moving east, the force exerted by the towline on the glider is directed east. By Newton's third law, the glider exerts an equal and opposite force on the towline.
Therefore, the glider exerts a force of 850 N on the towline and the force is directed to the west.