Final answer:
According to the Yerkes-Dodson law, performance during difficult tasks is related to arousal levels. Moderate levels of arousal tend to lead to the best performance, while both low and high arousal levels can hinder performance.
Step-by-step explanation:
According to the Yerkes-Dodson law, performance during difficult tasks is related to arousal in an inverted U-shaped curve. In simpler terms, moderate levels of arousal tend to lead to the best performance on difficult tasks. When arousal levels are too low, such as boredom or apathy, performance suffers. Likewise, when arousal levels are too high, such as extreme anxiety, performance also suffers.