Avertical piston-cylinder device initially contains a mixture of 2kg liquid water and 13 kg of vapor water. the piston-cylinder system is completely insulated. the mass of the piston maintains a constant pressure of 325kpa inside the cylinder. a valve is now opened, and steam at 2 mpa and 500°c is allowed to enter until all the liquid in the cylinder is vaporized (saturated vapor). assuming the surroundings to be at 25°c and 100kpa, find (a) the amount of steam that has entered and (b) the exergy destroyed during this process