The natural gas is ______than petroleum it floats above the petroleum deposits trapped beneath imprevious rocks.

Options

A. heavier
B. lighter
C. transparent
D. None of them

Answer

To solve the question "The natural gas is ______ than petroleum; it floats above the petroleum deposits trapped beneath impervious rocks," we need to understand the relationship between the densities of natural gas and petroleum.

### Step-by-Step Solution:

1. **Understanding the Question**: The question states that natural gas floats above petroleum deposits. This implies a comparison of density between the two substances.

2. **Density Concept**: Density is defined as mass per unit volume. A substance with a lower density will float on a substance with a higher density.

3. **Identifying the Substances**:
- **Natural Gas**: A gaseous fossil fuel that is lighter than many liquids.
- **Petroleum**: A liquid fossil fuel that is denser than natural gas.

4. **Analyzing the Information**: Since natural gas floats above petroleum, it indicates that natural gas is less dense than petroleum.

5. **Conclusion**: Therefore, we can fill in the blank in the question. The correct statement would be: "The natural gas is **lighter** than petroleum."

### Final Answer:
The natural gas is **lighter** than petroleum.

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