The electric field of an electromagnetic wave in free space is given by $\overrightarrow{E} = 10cos(10^7t +kx)\hat{j} \;V/m$ where t and $x$ are in seconds and metres respectively. It can be inferred that
(a) The wavelength λ is 188.4 m
(b) The wave number k is 0.33 rad/m
(c) The wave amplitude is 10 V/m
(d) The wave is propagating along +$x$ direction
Which one of the following pairs of statements is correct?