Which is the first energy level containing f-orbitals ?

Explanation

To determine the first energy level that contains f-orbitals, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Quantum Numbers**:
- The principal quantum number (n) indicates the energy level of an electron in an atom.
- The azimuthal quantum number (l) determines the shape of the orbital and can take values from 0 to (n-1).

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