1. Across 3 starts with 'n.'

2. 3 Across starts with 'n.'
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In a crossword puzzle, which one is correct?

#2 is correct.

To determine which clue is correct in the crossword puzzle, we can analyze the given information.

1. "Across 3 starts with 'n.'" This means that the answer to the clue in the 3rd position across (left to right) starts with the letter 'n'. However, the actual clue itself is missing.

2. "3 Across starts with 'n'." This means that the answer to the clue that starts in the 3rd position across (left to right) begins with the letter 'n'. In this case, the clue is provided and you can attempt to solve it using the available letters and the knowledge of the subject matter.

Based on the information provided, it seems like the second option, "3 Across starts with 'n'", is the correct one because it includes both the position and the provided letter.