Under which conditions can a rainbow be observed? Distinguish between primary and secondary rainbow.

Explanation

### Step-by-Step Solution

**Step 1: Conditions for Observing a Rainbow**
To observe a rainbow, two primary conditions must be met:
1. **Presence of Water Droplets**: There must be water droplets in the atmosphere, which can be from rain, mist, or spray.
2. **Position of the Sun**: The Sun must be positioned behind the observer. This means that the sunlight should be coming from behind the person looking for the rainbow.

**Step 2: Distinguishing Between Primary and Secondary Rainbow**
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