The two metal objects in the figure have net charges of +68 pC and -68 pC, which result in a 28 V potential difference between them.
(a) What is the capacitance in picofarads of the system?
(b) If the charges are changed to +220 pC and -220 pC, what does the capacitance in picofarads become?
(c) What does the potential difference become?