Write the range of frequencies of electromagnetic waves which propagate through sky wave mode.

Explanation

To determine the range of frequencies of electromagnetic waves that propagate through sky wave mode, we can follow these steps:

### Step 1: Identify the frequency range
The first step is to identify the specific frequency range that is used for sky wave propagation.

**Solution**: The range of frequencies for electromagnetic waves that propagate through sky wave mode is from **3 MHz to 30 MHz**.

### Step 2: Understand the significance of this frequency range
...