Answer true or false
Umbra is a region of complete darkness.

Explanation

**Step-by-Step Solution:**

1. **Understanding the Terms**: First, we need to understand what "Umbra" means. Umbra refers to the darkest part of a shadow where the light source is completely blocked by an object.

2. **Identifying the Characteristics of Umbra**: In the umbra, there is no light reaching that area because the light source is entirely obstructed. This results in complete darkness.

3. **Differentiating Between Umbra and Penumbra**: It is also important to differentiate umbra from penumbra. The penumbra is the area surrounding the umbra where only some light is blocked, resulting in partial darkness.

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