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Do you remember Circles?

Geometry Level 3

Find the magnitude of angle ABC in degrees if the radius of the circle is "r".

150 130 110 170 140 160 100 120

Excel in math and science

Master concepts by solving fun, challenging problems.

It's hard to learn from lectures and videos

Learn more effectively through short, conceptual quizzes.

Our wiki is made for math and science

Master advanced concepts through explanations,
examples, and problems from the community.

Used and loved by 4 million people

Learn from a vibrant community of students and enthusiasts,
including olympiad champions, researchers, and professionals.

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