State any two reason for necessity of modulation.

Explanation

### Step-by-Step Solution:

1. **Understanding Modulation**:
- Modulation is the process of varying certain parameters (amplitude, frequency, or phase) of a carrier wave in accordance with a modulating signal that carries information.

2. **Reason 1: Avoiding Mixing of Signals**:
- When baseband signals (like sound signals) are transmitted without modulation, they occupy a frequency range (typically 0 to 20 kHz). If multiple signals are transmitted simultaneously in this range, they can overlap and mix, making it difficult for the receiver to distinguish between them. Modulation helps to shift these signals to higher frequencies, thereby avoiding interference and allowing for clearer reception.

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