Calculate the energy released when an electron annihilates a positron.

Explanation

To calculate the energy released when an electron annihilates a positron, we can follow these steps:

### Step 1: Understand the mass-energy equivalence
The energy released during the annihilation can be calculated using Einstein's mass-energy equivalence formula:
\[ E = mc^2 \]
where:
- \( E \) is the energy,
- \( m \) is the mass that is converted into energy,
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