13. A garden pond has an area of 2 m2. How much energy would it require to raise the temperature of a pond of water 3 oC if the pond had a total volume of 1000 litres. Express your answer to the nearest calorie and joule. (2 marks). If it took 6 hours for the pond to warm by 3 oC, what was the energy storage during this period in units of W / m2 ? Express your answer to the nearest decimal. (2 marks).