A system contains a fluid at a temperature of \(70^{\circ} \mathrm{C}\) and 1 bar. It undergoes a reversible process during which the temperature of the system remains constant. Given that the heat transfer to the fluid during the process is \(100 \mathrm{~kJ}\), evaluate

a. the increase in entropy.

b. if the system has a mass of \(2.31 \mathrm{~kg}\). Evaluate the increase in specific entropy of the system.

c. If a second fluid system, identical to the first one undergoes an irreversible isothermal process from the same initial state to the same final state as above; and the heat transfer to the fluid in this irreversible process is \(180 \mathrm{~kJ}\); evaluate the increase in entropy of the fluid.

[0.2915 kJ/K; \(0.1262 \mathrm{~kJ} / \mathrm{kg} \mathrm{K;} 0.2915 \mathrm{~kJ} / \mathrm{kg} \mathrm{K}\) ]