1. The problem statement, all variables and given/known data How much kWh is beeing used to heat 285 liters of water in a water heater from: 1. + 5 °C to + 75 °C 2. + 20 °C to + 75 °C 2. Relevant equations Found this equation: kWh = (Q*CJ*∆t)/T 3. The attempt at a solution Q = liter = 285 Cj = heat capacity = 4,18 ∆t = 70 for 1. And 55 for 2. T = is the time, but I'm not sure what to use here, so I used 3600. So my answer was: 1. 23,2 kWh 2. 18,2 kWh I have no clue if this is right or wrong because of the variable T. What is correct here?