The correct percentage of `CO_(2)` in atmosphere is

Options

A. `0.03%`
B. `0.3%`
C. `1%`
D. `C^(14) and O^(18)`

Answer

To determine the correct percentage of CO2 in the atmosphere, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Composition of the Atmosphere**: The atmosphere is made up of various gases, with nitrogen, oxygen, argon, carbon dioxide, and water vapor being the primary components.

2. **Identify the Major Gases**:
- Nitrogen (N2) constitutes about 78% of the atmosphere.
- Oxygen (O2) makes up approximately 21%.
- Argon (Ar) is around 1%.
- Water vapor (H2O) can vary but is generally about 0.5%.
- Carbon dioxide (CO2) is present in much smaller quantities.

3. **Locate the Percentage of CO2**: From the information about atmospheric gases, carbon dioxide is present at a concentration of approximately 0.03%.

4. **Eliminate Incorrect Options**:
- The options provided were 0.03%, 0.3%, 1%, and C14 and O18.
- Since C14 and O18 are isotopes and not percentages, they can be disregarded.
- The other options (0.3% and 1%) are higher than the actual percentage of CO2.

5. **Conclude the Correct Answer**: The correct percentage of CO2 in the atmosphere is 0.03%.

### Final Answer:
The correct percentage of CO2 in the atmosphere is **0.03%**.

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