If the mass of an atom of `C-12` becomes half of its actual value then the atomic mass of phosphorous will change from 31 amu to what new value?

Explanation

To solve the problem, we need to understand how atomic masses are defined and how they relate to a reference standard.

### Step-by-Step Solution:

1. **Understanding Atomic Mass Units (amu)**:
- The atomic mass unit (amu) is defined based on the mass of the carbon-12 isotope. Specifically, 1 amu is defined as 1/12 of the mass of a carbon-12 atom.

2. **Current Mass of Carbon-12**:
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