The size of the umbra region can be varied by varying the distance between the _____ , ____ and _____

Explanation

To answer the question about how the size of the umbra region can be varied, we need to identify the three key components involved in shadow formation: the light source, the opaque object, and the screen. Here’s a step-by-step breakdown of the solution:

### Step-by-Step Solution:

1. **Identify the Components**:
- The three components involved in creating the umbra region are:
- **Source of Light**: This is where the light originates from.
- **Opaque Object**: This is the object that blocks the light and creates a shadow.
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