Answer 1

(a) increases
(b) decreases

Displacement current inside a capacitor,

`i_d = ∈_0 (dΦ_E)/dt` ,  Where

`Φ_E` is the electric flux inside the capacitor.
Up to the time the electric flux changes, there will be a displacement current. This is possible when the charge on a capacitor changes. Therefore, the displacement current goes through the gap between the plates of a capacitor when the charge of the capacitor or electric field increases or decreases inside the capacitor.