A site is underlain by a 10 meter layer of saturated gravel with unit weight = 20 kN/m3. Point A is located 5 meters below the ground surface. The horizontal effective stress at point A is 30 kPa. Determine the lateral stress ratio of the soil at point A.

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).