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Capacitors question

Area= 4x10^-2 m
Distance= 1.5mm
Potential difference= 500V

a)

i) Calculate capacitance= (8.85x10^-12)*A/d= 2.36x10^-10 F

ii) Calculate charge stored= CV = 1.18x10^-7 C

iii) Calculate energy stored= 0.5*C*V^2 = 2.95x10^-5 J

Okay so those 3 calculations were fine, it's the next one that I am having trouble with:

b) The plates are now disconnected from the supply and electrically isolated, the original charges remaining on them. The upper plate is then raised until the separation of the plates is 6.0mm.

i) calculate the increase in energy stored in the capacitor

So I worked out the new capacitance= (8.85x10^-12)*A/d= 5.9x10^-11 F

Then I did E= 0.5* Q^2/C = 0.5* (1.18x10^-7)^2/5.9x10^-11 = 1.18x10^-4 J

Then I did increase in energy= 1.18x10^-4 - 2.95x10^-5 = 8.85x10^-5 J

But the book says the answer is 1.2x10^-4 J???

Can someone please help me out
The book has clearly printed the wrong answer. It's printed the new energy rather than the increase.

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