Four people participate in a rope competition. Two of them pull the rope right, exerting forces of magnitude 330 N and 380 N . The other two pull left, exerting forces of magnitude 360N and 400N .

Part A

What is the sum of the forces exerted on a short section in the middle of the rope?
Express your answer to two significant figures and include the appropriate units. Enter positive value if the direction of the force is to the right and negative value if the direction of the force is to the left..