A jug contains 1 kg of water at 200 degrees Celsius. How much ice at 0 degrees Celsius must be added to the jug of water so that all of the ice melts and the system is at a final temperature of 0 degrees Celsius? If half this amount of ice is added to the jug, what will be the final temperature of the system?
[Ignore the specific heat of the jug and assume that the system is otherwise isolated.]