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This is Giancoli Answers with Mr. Dychko. so, a cycle could begin here, say at its maximum amplitude and it would travel back to the equilibrium position and then go a further distance equal to the amplitude again and then travel back and then return to its initial position and that's one full cycle. so that means it's traveled this amplitude four times, has traveled at once back to the equilibrium, once back to the equilibrium and then again to the farthest extent to the other side of equilibrium and then back to the equilibrium, then back to its initial position. so, that's four times amplitude, four times 0.21 0.84 meters is the total distance in one cycle.