Which of the following will increase the effects of alcohol and drugs when boating?

Increased effects of alcohol and drugs while boating are significantly influenced by vibration. When a vessel is in motion, the vibrations produced can intensify the impairing effects of substances on the body and mind. This is due to several factors, including how the body processes alcohol and drugs, which can be affected by the motion and jostling of the boat.

For example, the constant vibration can exacerbate feelings of disorientation and decrease overall coordination, further impairing a person's ability to operate the vessel safely. This means that even individuals who might normally have a certain level of tolerance could experience a more pronounced impairment due to the additional physical stresses from the boat’s movement.

In contrast, while temperature, wave height, and duration on the water can play roles in how a person may feel or react while boating, they do not have the same direct physiological correlation with the effects of alcohol and drugs as vibration does.