Answer: c) right
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Explanation:
This is another way of saying a 90 degree angle. The central angle of a semicircle is 180 degrees (which is half of a full circle at 360 degrees). The inscribed angle theorem says that the inscribed angle is half the central angle, so we take half of 180 to get 90.
This is Thales Theorem, which is a special case of the inscribed angle theorem.
