In an ECM operation the frontal working area of the electrode is 1555 mm2 . Applied current = 1200 amps and voltage = 12 volts. The material being cut is nickel (valence = 2). (a) If the process is 90% efficient, determine the rate of metal removal in mm3 /min. (b) If the electrolyte resistivity = 150 ohm mm, determine the working gap.