Final answer:
A muscle receiving 20 to 25 action potentials per second will contract more forcefully than a muscle receiving 10 to 15 action potentials per second due to the increased frequency and calcium flooding.
Step-by-step explanation:
The contraction force of a muscle is determined by the frequency of action potentials received by the myofibers from the neurons that control them. A higher frequency of action potentials results in a more forceful muscle contraction. This is due to the fact that at higher frequencies, myofibers are flooded with calcium which allows for increased force production by the muscle. Thus, a muscle receiving 20 to 25 action potentials per second would contract more forcefully compared to a muscle receiving 10 to 15 action potentials per second.