Electrolytes of two redox couples $Z{n}^{+2}/Zn$ and $C{u}^{+2}/Cu,$ in the standard state, are connected by a salt bridge , containing Potassium chloride , and corresponding metal rods by a copper wire. Choose the correct option(s):

Current flows from Zinc electrode to Copper electrode in the metallic wire

Salt bridge is necessary to maintain potential difference across the electrodes until equilibrium is attained

Current flows in the direction, anode to cathode through the salt bridge.

Potential difference across the two electrodes is equal to double the electro motive force of the cell