A tank has a stirrer that delivers 200 kJ of work on 100 kilograms of water at 45 degrees Celcus. Assume all of the work done by the stirrer is transferred to the water and the tank does not change temperature with the water. Find:
A.) the change of internal-energy of the water
B.) final temperature of the water
C.) If we were told that the water will reach a temperature of 46 degrees Celcius if the stirrer was 100% efficient in this situation, what is the actual efficiency of our stirrer?