Capacitors question

There are 10uF, 20uF and 30uF capacitors in parallel and hooked up to a 10V battery how do you work out energy stored in each capacitor? Then the same capacitors are now connected in series how do you work out the energy stored in each capacitor now?

Hello and welcome to TSR.

If you are doing this for A-level (please confirm) then you won't need to know how to derive this (involves integration) but you do need to know the equation for energy stored on a capacitor:

for part a)

E = (CV²)/2

for part b)

you need to work out the voltage developed across each series capacitor and then use the equation in part a).