# A wave travelling along the x-axis is described by the equation y(x, t) = 0.005 cos ($\alpha x-\beta t$). If the wavelength and the time period of the wave are 0.08 m and 2.0 s, respectively, then $\alpha$ and $\beta$ in appropriate units are
( A ) $\alpha=12.50\pi,\beta=\frac{\pi}{2.0}$
( B ) $\alpha=\frac{0.04}{\pi},\beta=\frac{1.0}{\pi}$
( C ) $\alpha=\frac{0.08}{\pi},\frac{2.0}{\pi}$
( D ) $\alpha = 25.00 \pi$, $\beta =\pi$