Can an object be at rest if forces are being applied to it? Explain.

1. A horizontal force of 250 N is applied to a stationary wooden box in one direction, and a 600-N horizontal force is applied in the opposite direction. What additional force is needed for the box to remain stationary?

1. Determine the net force necessary to give an object with a mass of 4.0 kg an acceleration of 5.0m/s^2.

1. 4. A 1000-kg automobile is pulled by a horizontal towline with a net force of 950 N. What is the acceleration of the auto? (Neglect friction.)