Final answer:
The net force experienced by a water-skier traveling forward at constant speed is zero, signifying balanced forces in accordance with Newton's first law of motion.
Step-by-step explanation:
If a water-skier is traveling forward in a straight line at constant speed, the net force she experiences is zero. This is due to Newton's first law of motion, which states that an object in motion will remain in motion with a constant velocity (which includes at rest) unless acted upon by a net external force. In this scenario, the forces are balanced because the forward force provided by the boat is exactly equal to the resistive forces acting on the skier, such as water resistance and possibly air resistance.