The Heating Coil of a Hot Water Heater Has a Resistance

Short Answer

The heating coil of a hot water heater has a resistance of 20 ohms and operates at 210 V.If electrical energy costs 5.5 cents per kW-hr,what does it cost to raise the 200 kg of water in the tank from 15 $\degree$ C to 80 $\degree$ C? (The specific heat of water is 4 186 J/kg $\degree$ C)