A three bladed wind turbine has a small unbalanced mass m = 0.1 kg located at radius r=0.1m in the plane of the blades. The blades are located from the central vertical (y) axis at a distance R=0.5m and rotate at an angular velocity of 31.413 rad/s. If the supporting truss can be modeled as a hollow steel shaft of out diameter 0.1m and inner diameter 0.08m, determine the maximum stress at the base of the support (point A). The mass moment of inertia of the turbine system about the vertical y axis is 100 kg-m2. The height of the rob to the center of the blade hub is 8m.