`""_(4)^(7)Be` captures a K-electron into its nucleus. What will be the mass number and atomic number of the nuclide formed?

Explanation

To solve the problem, we need to analyze the process of electron capture in the context of the given nuclide, which is beryllium-7 \((^{7}_{4}Be)\).

### Step-by-Step Solution:

1. **Identify the Initial Nuclide**:
The initial nuclide is beryllium-7, which has:
- Atomic number (Z) = 4
- Mass number (A) = 7
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