Given wave function for a wave to be $\psi(x, t)=10^3 \sin \left(3 \times 10^6 x-9 \times 10^{14} t\right)$ The speed of the wave is

$3 \times 10^8 m / s$ $2 \times 10^8 m / s$ $10^8 m$ $6 \times 10^8 m / s$

$3 \times 10^8 m / s$

$c=\omega / k=\frac{9 \times 10^{14}}{3 \times 10^6}=3 \times 10^8$ ∴ (A)