Final answer:
To reduce a high fever, placing the person in a 30 degrees C tub for 10 minutes may be more effective than shorter exposures to colder water. This method allows sufficient time for heat to transfer without shocking the body.
Step-by-step explanation:
When treating a person with a high fever, such as 104 degrees F (40 degrees C), the goal is to lower the body temperature safely and effectively. Immersing a person in cool water can facilitate this process through the principle of heat transfer. The effectiveness of cooling depends on several factors, including the temperature difference between the person's body and the water, the duration of exposure, and the surface area in contact with the water.
Of the given options, placing the person in a 20 degrees C tub of water for 1 minute will not be as effective due to the short exposure time. Placing the person in a 25 degrees C tub for 5 minutes might be more effective than 1 minute at 20 C, but the best option would likely be the 30 degrees C tub for 10 minutes. This provides a longer period for heat transfer while not being so cold as to cause a shock to the system.
It's important to cool the person gradually to prevent hypothermia or shock. Moreover, the human body can respond effectively to short-term exposure to both heat and cold by regulating mechanisms such as sweating. However, in a high fever situation, internal regulation may not be adequate, and external cooling methods are necessary.