Physics
posted by P .
A capacitor consists of two concentric spherical shells. The outer radius of the inner shell is a=0.43 mm and the inner radius of the outer shell is b=2.2 mm .
(a) What is the capacitance C of this capacitor? Express your answer in Farads.
incorrect
(b) Suppose the Maximum possible electric field at the outer surface of the inner shell before the air starts to ionize is Emax(a)=3.0*10^6V/m. What is the maximum possible charge on the inner sphere? Express your answer in Coulombs.
incorrect
(c) What is the maximum amount of energy stored in the capacitor? Express your answer in Joules.
incorrect
(d) When Ea)=3.0*10^6V/m what is the absolute value of the potential difference between the shells? Express your answer in Volts.

Please someone answer.