The net optical rotation of meso-tartaric acid is ......... due to ........ compensation.

Explanation

To solve the question regarding the net optical rotation of meso-tartaric acid, we can break it down into a step-by-step explanation.

### Step-by-Step Solution:

1. **Understanding Meso Compounds**:
Meso compounds are achiral molecules that contain stereocenters. They have an internal plane of symmetry that allows one half of the molecule to be a mirror image of the other half.

**Hint**: Recall that meso compounds have a plane of symmetry which contributes to their optical properties.
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