c
(c) A wave travelling in positive $x-$direction may be represented as
$y = A\sin \frac{{2\pi }}{\lambda }\,(v\,t - x)$.
On putting values $y = 0.2\sin \frac{{2\pi }}{{60}}(360\,t - x)$
$\Rightarrow$ $y = 0.2\sin 2\pi \,\left( {6\,t - \frac{x}{{60}}} \right)$