The layer containing petroleum oil and gas is present________that of water.

Options

A. beneath
B. below
C. above
D. None of them

Answer

To answer the question "The layer containing petroleum oil and gas is present ______ that of water," we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Composition of Layers**:
- We need to identify the layers involved: the layer of water, the layer of petroleum oil, and the layer of gas.

2. **Density Comparison**:
- We know that the density of petroleum oil is less than that of water. This means that petroleum will float on water.
- The density of gas (natural gas) is even less than that of petroleum oil, which means that gas will rise above the petroleum layer.

3. **Layer Arrangement**:
- Since petroleum oil is less dense than water, it will be found above the water layer.
- The gas, being the least dense, will be found above the petroleum layer.

4. **Final Arrangement**:
- Therefore, the arrangement from bottom to top is: water at the bottom, followed by petroleum oil, and then gas at the top.

5. **Answer the Question**:
- Since the layer containing petroleum oil and gas is above the layer of water, we can fill in the blank: "The layer containing petroleum oil and gas is present **above** that of water."

### Final Answer:
The layer containing petroleum oil and gas is present **above** that of water.

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