A typical cell membrane is 8.0 nm thick and has an electrical resistivity of 1.3 × 107 Ω ( m.

(a) If the potential difference between the inner and outer surfaces of a cell membrane is 75 mV, how much current flows through a square area of membrane 1.0 (m on a side?

(b) Suppose the thickness of the membrane is doubled, but the resistivity and potential difference remain the same. Does the current increase or decrease? By what factor?