Consider the cyclic process \( \mathrm{R} \rightarrow \mathrm{S} \rightarrow \mathrm{R} \) as sh...

Consider the cyclic process \( \mathrm{R} \rightarrow \mathrm{S} \rightarrow \mathrm{R} \) as shown in the Fig. You are told that one of the path is adiabatic and the other one isothermal. Which one of the following is(are) true?
- (a) Process \( \mathrm{R} \rightarrow \mathrm{S} \) is isothermal
(b) Process \( \mathrm{S} \rightarrow \mathrm{R} \) is adiabatic
(c) Process \( \mathrm{R} \rightarrow \mathrm{S} \) is adiabatic
(d) Such a graph is not possible