I bought a 2013 MacBook Air on Friday, June 28th,
i used it for 4 days, then i found a black spot on the screen.
should i go to the store to ask for a new one?
If the spot concerns you (as it sounds like it does), sure, you should take it to the Store.
All the best - I believe if you take it to an Apple Store (assuming you bought it directly from Apple), they will take good care of you and remedy the situation one way or another.
Thanks a lot
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