Electrical Engineering - Design Problem - Capacitors

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Problem
Given the power that is needed to be output by the capacitor - P
the length of time that the capictor must give off that power - t
the maximum operation voltage that the capacitor can operate at- V
the dialectric constant of several materials - ε
the breakdown field of those several materials - [itex]U_{d}[/itex]
and the mass density of those several materials - ρ
Design the capacitor that meets these requirements

Dialectic Material 1
ε= [itex]4ε_{0}[/itex]
[itex]U_{d} = 1 \frac{V}{nm}[/itex]
[itex]ρ = 2.5 \frac{g}{cm^{3}}[/itex]

Dialectic Material 2
ε= [itex]80ε_{0}[/itex]
[itex]U_{d} = .03 \frac{V}{nm}[/itex]
[itex]ρ = 1 \frac{g}{cm^{3}}[/itex]

Dialectic Material 3
ε= [itex]200ε_{0}[/itex]
[itex]U_{d} = .1 \frac{V}{nm}[/itex]
[itex]ρ = 1 \frac{g}{cm^{3}}[/itex]

Metal 1
[itex]ρ=2.7 \frac{g}{cm^{3}}[/itex]

Metal 2
[itex]ρ=2.1 \frac{g}{cm^{3}}[/itex]

The machine which can make the capacitor has the following thickness restrictions
[itex]10 nm < t_{dialectic}< 10 μm[/itex]
[itex]10 μm < t_{dialectic}< 10 cm[/itex]

Equations
[itex]C = \frac{εA}{d}[/itex]
[itex]C = \frac{dQ}{dV}[/itex]
[itex]U = \frac{dW}{dt}[/itex]
the maximum energy stored in a capacitor is below
[itex]w = \frac{1}{2}εCd^{2}U_{d}^{2}[/itex]
[itex]V = U_{d}d[/itex]
[itex]U=CV(t)\frac{dV}{dt}[/itex]
[itex]U=\frac{1}{2}CV^{2}[/itex]
[itex]I=\frac{dQ}{dt}[/itex]
[itex]hp ≈ 746 W[/itex]
[itex]ε_{0} ≈ 8.85*10^{-12} \frac{F}{m}[/itex]
[itex]m = 10^{9} nm[/itex]
[itex]m = 10^{6} μm[/itex]
[itex]m = 10^{3} cm[/itex]
[itex]kg = 1000 g[/itex]

Attempt at a solution
I have no idea how to do this at all or where to begin. I just randomly chose material 3 for the dielectric material and started solving and go the following relations.

C = 3.082644628 F
Q = 678.1818182 C
[itex]w = 10 ε_{0}Cd^{2}[/itex]

I don't know where to go from here or if I'm even on the right track at all. Thanks for any help that anyone can provide. It would be greatly appreciated.

Thanks!
 
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