Which range of frequencies can be transmitted suitable by sky wave propagation?

Options

A. 5kHz to 500 kHz
B. 1MHz to 2 MHz
C. 2 MHz to 20 MHz
D. Above 50 MHz

Answer

### Step-by-Step Solution:

1. **Understanding Sky Wave Propagation**:
Sky wave propagation refers to the transmission of radio waves that are reflected back to Earth by the ionosphere. This method is commonly used for long-distance communication.

2. **Identifying Frequency Ranges**:
The frequencies suitable for sky wave propagation typically fall within a specific range. The ionosphere can effectively reflect radio waves within certain frequency bands.

3. **Common Frequency Ranges**:
- The frequency range that is generally accepted for effective sky wave propagation is **5 MHz to 25 MHz**.
- Additionally, frequencies in the range of **1 MHz to 2 MHz** can also be utilized for sky wave propagation, but they are less commonly used.

4. **Conclusion**:
Therefore, the suitable frequency ranges for sky wave propagation are **5 MHz to 25 MHz** and **1 MHz to 2 MHz**.

### Final Answer:
The range of frequencies suitable for sky wave propagation is **5 MHz to 25 MHz** and **1 MHz to 2 MHz**.

---