Record be2c3fa3308a4c248984ad1d9baea3b5

Ultra reads the prompt, this answer, the verified correct answer and the difficulty settings, then explains the mistake. The verifier's own classification is shown next to it for comparison.

At 8:00, Sofia brought the heavy tablet over to the reception area. At 8:00, Petra was nearby and saw this happen. At 8:01, Sofia moved the heavy tablet into the archive room. At 8:01, Petra was nearby and saw this happen. At 8:02, Sofia brought the heavy tablet over to the atrium. At 8:02, Petra happened to be watching. At 8:03, Sofia moved the heavy tablet into the archive room. At 8:03, Petra was nearby and saw this happen. At 8:04, Sofia took the heavy tablet and placed it in the meditation room. At 8:04, Petra happened to be watching. At 8:05, she brought the heavy tablet over to the atrium. At 8:06, Sofia carried the heavy tablet to the archive room. At 8:06, Petra noticed this from across the room. At 8:07, Sofia brought the heavy tablet over to the security office. At 8:08, Uma moved the blue box into the atrium. At 8:09, Petra took the blue box and placed it in the cafeteria. At 8:10, Sofia reorganized some papers on the desk. At 8:11, Uma refilled a cup of coffee. At 8:12, Petra checked their email.

Where does Petra believe the heavy tablet is? Answer with only the location name (or 'unknown' if they have no belief).

security office

(no reasoning captured)