An insulated container filled with 25 kg of water at 20 ℃ is fitted with a stirrer, which is made to turn by gravity acting on a weight of mass 35 kg. The weight falls slowly through a distance of 5 m, driving the stirrer. Assuming that all work done on the weight is transferred to the water, the container changes in temperature along with the water, the water has �# ! = 4.18 kJ⋅kg-1 ℃-1, the container has a heat capacity equivalent to 5 kg of water, and the local acceleration due to gravity is 9.8 m s-2 , determine: a. (5 points) The amount of work done on the system (water + container) b. (5 points) The internal energy change of the system c. (5 points) The final temperature of the system d. (5 points) The amount of heat that must be removed from the system to return it to its initial temperature