The interplanar separation between fixed square plates of an initially air-filled parallel plate capacitor is d and the plate area is  $A={\mathcal{l}}^2$ . A cuboidal shaped dielectric of dielectric constant K that has same dimension as that of interplanar gap of capacitor. An external agent slowly inserts this dielectric slab inside the capacitor till it completely fills the interplanar gap. An ideal cell of emf V is always connected across the capacitor as shown. All quantities are given in SI units. Pick up correct option(s).