Awater reservoir contains 108 metric tons of water at an average elevation of 84 m. the maximum amount of electric energy that can be generated from this water is: 8 kwh, 16 kwh, 1630 kwh, 16300 kwh or 58800 kwh.

Precipitation hardening can be achieved in many light alloys by a three-step heat treatment. what is carried out and what is the purpose at each step? why is such a treatment necessary based on the nucleation and growth theory of phase transformation. compare this treatment with tempering martensite for carbon steels (similarities and differences).