Name the thermometer which can automatically record the highest and lowest temperatures reached during the whole day.

Answer

To answer the question about the thermometer that can automatically record the highest and lowest temperatures reached during the whole day, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks for a specific type of thermometer that records the maximum and minimum temperatures over a day.

2. **Identifying Thermometers**: There are various types of thermometers used for measuring temperature, such as digital thermometers, mercury thermometers, and alcohol thermometers.

3. **Focusing on the Functionality**: The key feature we need is the ability to record both the highest and lowest temperatures automatically throughout the day.

4. **Recognizing the Right Thermometer**: The thermometer that fits this description is called the "maximum and minimum thermometer."

5. **Conclusion**: Therefore, the answer to the question is that the thermometer which can automatically record the highest and lowest temperatures reached during the whole day is the **maximum and minimum thermometer**.