the answers are

a) 12 kJ (approximately)

b) 6 kJ (approximately)

c) -1 kJ (approximately)

1 mol of steam is initially at 10bar and 200C. The surroundings are at 20C and 1 bar. (a) Calculate the exergy of the system. (b) Calculate the change in exergy for a process where the steam is heated at constant pressure until the volume doubles. (c) Calculate the change in exergy for a process where the steam isothermally expands until its volume doubles