In the process of going from the configuration depicted in Figure ($a$) to that in Figure ($b$), which of the following statement($s$) is(are) correct?
$E_0=\frac{V}{d} ; C=\frac{K \varepsilon_0 A}{d}$ For figure$(b)$
$C ^{\prime}=\frac{\varepsilon_0 A }{2 d - d + d / k } ;$
$C ^{\prime}=\frac{ K \varepsilon_0 A }{( K +1) d } ; C ^{\prime}=\frac{ C }{ K +1}$



