You are responsible for designing a heat engine. To achieve the required efficiency, the engine's hot reservoir acts at $475^\circ\mathrm{C}$ where the molar volume is $0.0001\ \mathrm{m^3}$. Using your knowledge of thermodynamics select an appropriate material to construct your engine based on the Maximum Allowable Operating Pressures presented in Table 1. Present all your working and justify any assumptions made. Table 1: Maximum Allowable operating Pressures for a selection of generic materials (MPa): A 20; B 30; C 35; D 42; E 65; F 74. The critical temperature and pressure for the working fluid are $374^\circ\mathrm{C}$ and 22.12 MPa respectively and the acentric factor is 0.187.

Calculate the work done by the engine if the cold reservoir is at room temperature ($25^\circ\mathrm{C}$), the total entropy generated during the cycle is $30{,}000\ \mathrm{kJ\,K^{-1}}$ and the heat deposited from the hot reservoir is 160,000 kJ.