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Kneel for 20 12 Xicheng district senior high school entrance examination [mathematics] [as long as 2 1 questions are rounded]
As shown in the figure, AC is the diameter ⊙O, AC=4, B and D are on the circles on both sides of AC, ∠ Bad = 60, and the intersection of BD and AC is E.

(1) Find the distance from point O to BD and the number of times ∠OBD;

(2) If DE=2BE, find the value and length of CD.