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Which of the following wave equations describes a wave with a period of $3.5$ $s$?

$y(0,t)=1.0\cos (0.29\cdot t)$

$y(0,t)=2.5\cos (3.5\cdot t)$

$y(0,t)=3.0\cos (1.8\cdot t)$

$y(0,t)=3.5\cos (0.56\cdot t)$