Draw a diagram to show the energy changes in an oscillating simple pendulum. Indicate in your diagram how the total mechanical energy in it remains constant during the oscillation.

Explanation

To solve the problem of illustrating the energy changes in an oscillating simple pendulum and indicating how the total mechanical energy remains constant, we can follow these steps:

### Step-by-Step Solution:

1. **Draw the Pendulum**: Start by sketching a simple pendulum. This consists of a mass (the bob) attached to a string or rod, which is fixed at one end.

2. **Label Positions**: Identify and label three key positions of the pendulum:
- **Point A**: The left extreme position.
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