What causes the force that moves a boat forward when someone rows it? a. the force is caused by the rower's arms. b. the force is caused by an interaction between the oars and gravity. c. the force is caused by an interaction between the oars and the water the boat is traveling in. d. the force is caused by friction?

The answer is letter d. According to Newton’s first law, an object in motion will stay in motion and an object at rest will stay at rest unless acted upon by an outside force. Putting this concept in our problem, the boat will just stay put unless a force is applied to it and once it’s in motion, it will stay in motion because of friction unless a force is applied to it to stop.