Fill the missing word in the blank spaces in the following statements:
Near the earth's surface `ul("warm")` air rises up whereas _______ air comes down.

Explanation

To fill in the missing word in the statement, we can follow these steps:

1. **Understand the context**: The statement discusses the behavior of air near the Earth's surface, specifically mentioning warm air and what happens to it.

2. **Identify the properties of air**: Warm air is lighter and tends to rise, while cooler air is denser and tends to sink.

3. **Complete the statement**: Given that warm air rises, the air that comes down must be the cooler air. Therefore, the missing word in the statement is "cool".

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