The electric field associated with an electromagnetic wave propagating in a dielectric medium is given by \( \vec{E} = 30 ( 2\hat{x} + \hat{y} ) \sin \left[ 2\pi \left( 5\times 10^{14} t - \dfrac{10^{7}}{3} z \right) \right] \, \text{V m}^{-1} \). Which of the following option(s) is (are) correct?
[Given: The speed of light in vacuum, \( c = 3 \times 10^{8} \, \text{m s}^{-1} \)]