How many electrons are present in all subshells (fully - filled) with `n + l = 5` ?

Explanation

To find the number of electrons present in all subshells that are fully filled with \( n + l = 5 \), we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the \( n + l \) Rule**:
The \( n + l \) rule helps us determine the order of filling of atomic orbitals. Here, \( n \) is the principal quantum number and \( l \) is the azimuthal quantum number.

2. **Identifying Possible Values**:
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