He had solved thirty-two problems on regenerative cycles, reheat factors, and nozzle efficiencies. But this one was different. It described a combined cycle plant: a gas turbine topping a steam turbine, with an intercooler, reheater, and a heat recovery steam generator. The data was messy—inlet temperatures, pressure ratios, isentropic efficiencies, pinch points. And at the bottom, a deceptively simple question: “Determine the net work output and thermal efficiency. Comment on the feasibility of the cycle.”

Page 133. Problem 3(b). Marked “HOT” in the margin—High-Order Thinking.

He began, methodically. Gas turbine first: compressor work, combustion chamber heat addition, turbine expansion. Then exhaust gases—still scorching at 550°C—feeding the HRSG. Steam at 60 bar, 480°C, expanding through the steam turbine, then condensing, then back to the HRSG.