Summarize the development of accurate mechanical clocks from early civilizations through the Middle Ages.

Asteam turbine is supplied with steam at 28bar and 425c. a fraction of the steam is extracted at 1.2bar to heat the feed water in one open feed water heater. the rest of the steam expands in the low pressure stage of the turbine to 0.08bar. a)-sketch the regenerative rankine cycle with open feed water heater on the t-s diagram. b)-assuming isentropic expansion in both stages of the turbine, find the cycle efficiency. do not assume negligible pump work.