According to Maxwell,which is the missing term in Maxwell-Ampere circuital law?

Sea water at frequency $v = 4 \times 10^8\, Hz$ has permittivity $\epsilon \approx 80\epsilon_0$,permeability $\mu = \mu_0$ and resistivity $\rho = 0.25\,\Omega m$. Imagine a parallel plate capacitor immersed in sea water and driven by an alternating voltage source $V(t) = V_0 \sin(2\pi vt)$. What fraction of the conduction current density is the displacement current density?

Who produced electromagnetic waves for the first time?

Show that the magnetic field $B$ at a point in between the plates of a parallel-plate capacitor during charging is $B = \frac{{\mu _0 \epsilon _0 r}}{2} \cdot \frac{{dE}}{{dt}}$ (symbols have their usual meanings).

Match the following List-$I$ with List-$II$.

$A$. $\oint E \cdot dA$	$(i)$ $0$
$B$. $\oint B \cdot dA$	$(ii)$ $-\frac{d\phi_B}{dt}$
$C$. $\oint E \cdot dl$	$(iii)$ $\frac{Q}{\varepsilon_0}$
$D$. $\oint B \cdot dl$	$(iv)$ $\mu_0(i_c + i_d)$

$A$ plane electromagnetic wave of angular frequency $\omega$ propagates in a poorly conducting medium of conductivity $\sigma$ and relative permittivity $\varepsilon$. Find the ratio of conduction current density and displacement current density in the medium.