Suppose that the electric field part of an electromagnetic wave in vaccum is $E= 3.1 \times N/c $ an $[(1/8 rad/m)y +(5.4 \times 10^8\;rad/s/t)$ what is the direction of motion ?

Question

$\begin{array}{1 1} - \hat j \\ - \hat k \\ -\hat i \\ none\;of \;the \;above \end{array} $