Displacement of a wave is expressed as \( x(t) = 5 \cos\!\left(628 t + \frac{\pi}{2}\right) \, \text{m} \). The wavelength of the wave when its velocity is \( 300 \, \text{m/s} \) is: \( (\pi = 3.14) \)
\( 0.5 \, \text{m} \)
\( 3 \, \text{m} \)
\( 0.33 \, \text{m} \)
\( 5 \, \text{m} \)