A homemade capacitor is assembled by placing two 9-in. pie pans 4 cm apart and connecting them to the opposite terminals of a 9-V battery. Estimate
(a) The capacitance,
(b) The charge on each plate,
(c) The electric field halfway between the plates,
(d) The work done by the battery to charge them.
(e) Which of the above values change if a dielectric is inserted?