Following operations can be performed on a capacitor : $X$ - connect the capacitor to a battery of $emf$ $E.$ $Y$ - disconnect the battery $Z$ - reconnect the battery with polarity reversed. $W$ - insert a dielectric slab in the capacitor
AThe electric field in the capacitor after the action $ XW$ is the same as that after $ WX$.
BThe charge appearing on the capacitor is greater after the action $XWY$ than after the action $XYW$.
CThe electric energy stored in the capacitor is greater after the action $WXY $ than after the action $XYW.$
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