To calculate the efficiency of the electrochemical cell, we need to consider both the Faraday efficiency and the voltage efficiency.Faraday efficiency FE is the efficiency with which charge is transferred in a system facilitating an electrochemical reaction. In this case, the Faraday efficiency is 79%.Voltage efficiency VE is the efficiency with which the potential difference voltage is utilized in the electrochemical cell. In this case, the voltage efficiency is 85%.The overall efficiency of the electrochemical cell can be calculated by multiplying the Faraday efficiency and the voltage efficiency:Efficiency = Faraday Efficiency Voltage EfficiencyEfficiency = 0.79 0.85Efficiency = 0.6715 or 67.15%So, the efficiency of the electrochemical cell is 67.15%.