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3. A bug starts at a vertex of an equilateral triangle. On each move, it selects one of the two vertices where it is not currently located, with equal probability, and crawls along a side of the triangle to that vertex. Let p denote the probability that the bug moves to its starting vertex on its &th move. What are the values of P1; P2, Pa, pa, and p;? Express the answers in the simplest fractional form