Fill in the following blanks with suitable words :
Warm air is ______ than cold air.

Answer

To fill in the blank in the sentence "Warm air is ______ than cold air," we need to consider the properties of warm and cold air.

1. **Understanding the Properties of Air**: Warm air is known to have different characteristics compared to cold air. One key property is density.

2. **Density Comparison**: Warm air is less dense than cold air. This means that for the same volume, warm air weighs less than cold air.

3. **Using the Correct Term**: Since we are looking for a word that describes warm air in relation to cold air, we can use the term "lighter." This is because lighter air has lower density.

4. **Filling in the Blank**: Therefore, the completed sentence will read: "Warm air is lighter than cold air."

Final Answer: Warm air is **lighter** than cold air.

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