What is the sine of the angle measuring 30 degrees on the unit circle?
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What is the equation of a parabola that opens downward, with its vertex at (2, 5) and passing through the point (4, 1)?
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Math question: In triangle ABC, the angle bisector of angle A intersects side BC at point D. If the length of AD is 6 cm and BD is 8 cm, what is the length of DC?