ANSWER
[tex]\begin{equation*} 2.1*10^6\text{ V/m} \end{equation*}[/tex]EXPLANATION
To find the electric field amplitude, apply the relationship between electric field and magnetic field:
[tex]E=cB[/tex]where c = speed of light
B = magnetic field amplitude
Therefore, the electric field amplitude is:
[tex]\begin{gathered} E=3*10^8*7*10^{-3} \\ \\ E=2.1*10^6\text{ V/m} \end{gathered}[/tex]That is the answer.
