I'm not sure but I know u is 10^6
This question apparently comes after an EARLIER one,
where you were told either the voltage across the same
capacitor or the total charge stored in it. You can't answer
THIS one without that information.
You have to figure it out
what happens at Point C is sublimation. the increase in temperature affects the Vapour pressure soon as you can see the curve is increasing with increasing pressure there is increase in temperature that is the sublimation Curve
