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(D) Comparing the given equation $\vec{E} = 10 \cos(10^7t + kx) \hat{j} 	ext{ V/m}$ with the standard form $\vec{E} = E_0 \cos(\omega t + kx) \hat{j}

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$(i)$ and $(iii)$

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(D) Comparing the given equation $\vec{E} = 10 \cos(10^7t + kx) \hat{j} 	ext{ V/m}$ with the standard form $\vec{E} = E_0 \cos(\omega t + kx) \hat{j}$,we get:$E_0 = 10 	ext{ V/m}$ and $\omega = 10^7 	ext{ rad/s}$.$(i)$ Wavelength $\lambda = \frac{2\pi c}{\omega} = \frac{2 	imes 3.14 	imes 3 	imes 10^8}{10^7} = 188.4 	ext{ m}$. This is correct.$(ii)$ Wave vector $k = \frac{\omega}{c} = \frac{10^7}{3 	imes 10^8} = 0.033 	ext{ rad/m}$. This is incorrect (given $0.33 	ext{ rad/m}$).$(iii)$ Amplitude $E_0 = 10 	ext{ V/m}$. This is correct.$(iv)$ Since the argument is $(\omega t + kx)$,the wave propagates in the negative $X$-direction. This is incorrect.Thus,statements $(i)$ and $(iii)$ are correct.

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