Fluorine can be prepared by heating NaF and `MnO_2` with conc. sulfuric acid.

Explanation

To determine whether fluorine can be prepared by heating NaF and MnO2 with concentrated sulfuric acid, we can analyze the reaction step by step.

### Step 1: Understand the Reactants
- **NaF (Sodium Fluoride)**: This is a salt that contains fluoride ions (F⁻).
- **MnO2 (Manganese Dioxide)**: This is an oxide of manganese that can act as an oxidizing agent.
- **Concentrated Sulfuric Acid (H2SO4)**: This is a strong acid that can facilitate various chemical reactions.

### Step 2: Analyze the Reaction
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