Give the advantages of selecting wavelength of light as a standard of length.

Explanation

To answer the question regarding the advantages of selecting the wavelength of light as a standard of length, we can break down the advantages into clear points:

### Step-by-Step Solution:

1. **Invariant Quantity**:
- The wavelength of light is considered an invariant quantity. This means that it does not change regardless of the conditions under which it is measured. This stability makes it a reliable standard for length measurements.

2. **Independence from External Conditions**:
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