Observerare

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  Buck Gutteridge

  https://quizzy.us/%EB%85%B8%EB%9E%98%EC%A3%BC%EC%A0%90%EC%95%8C%EB%B0%94%EC%9D%98-%EB%A7%A4%EB%A0%A5%EC%9D%84-%ED%83%90%EA%B5%AC%ED%95%98%EB%8B%A4/