In `C^(12)` atom if mass of `e^(-)` is doubled and mass of proton is halved, then calculate the percentage change in mass no. of `C^(12)`

Explanation

To solve the problem, we need to analyze the changes in the masses of the particles in the carbon-12 atom and then calculate the percentage change in the mass number.

### Step-by-step Solution:

1. **Identify the components of Carbon-12 (C-12)**:
- Carbon-12 has:
- 6 protons
- 6 neutrons
...