The electric field of an electromagnetic wave in free space is given by $\overrightarrow E = 10\cos ({10^7}t + kx)\widehat j\,\,V/m,$ where t and x are in seconds and metres respectively. It can be inferred that
(1)  the wavelength $\lambda $ is 188.4 m.
(2)  the wave number k is 0.33 rad/m.
(3)  the wave amplitude is 10 V/m.
(4)  the wave is propagating along +x direction.

Which one of the following pairs of statements is correct ?