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A plane wave of wavelength $\lambda$ is travelling in a direction making an angle $30^{\circ}$ with positive $x$-axis and $90^{\circ}$ with positive $y$-axis. The $\vec{E}$ field of the plane wave can be represented as ( $E_{0}$ is a constant)

1. $\vec{E}=\hat{y} E_{0} e^{j\left(\omega t-\frac{\sqrt{3} \pi}{\lambda} x-\frac{\pi}{\lambda} z\right)}$
2. $\vec{E}=\hat{y} E_{0} e^{j\left(\omega t-\frac{\pi}{\lambda} x-\frac{\sqrt{3} \pi}{\lambda} z\right)}$
3. $\vec{E}=\hat{y} E_{0} e^{j\left(\omega t+\frac{\sqrt{3} \pi}{\lambda} x+\frac{\pi}{\lambda} z\right)}$
4. $\vec{E}=\hat{y} E_{0} e^{j\left(\omega t-\frac{\pi}{\lambda} x+\frac{\sqrt{3} \pi}{\lambda} z\right)}$