1. The problem statement, all variables and given/known data

The figure shows the circuit of a flashing lamp.There is a current through the lamp (see the photo) only when the potential difference across it reaches the breakdown voltage VL; the capacitance DIScharges completely through the lamp.

(a)A lamp has breakdown voltage VL=72V and is wired to a 95V ideal battery and a capacitor of 0.15 μF. The lamp flashes two times per second. Sketch how the voltage across the capacitor changes over 3 seconds. Neglect the period of time that it takes to discharge.
(b) What resistance is needed for two flashes per second?
(c) How much energy is released through the lamp per flash?

2. Relevant equations

E=0.5CV^2
V=ε(1-e^-(t:RC))

3. The attempt at a solution
I have solved (b), i got 3.25*10^6 ohm. However, I am having difficulty with the sketch. How does it look like, should I use the second formula I mention in 2. Relevant equations? What should I do with the information ‘ discharge’ ?
Furthermore, as I already figured out the resistance needed for two flashes, is this relevant for how mudh energy is released? Or is it just a basic solution like: E=0.5*0.15*10^-6*72^2 ?

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