Solve the following problem:
Consider a plane defined in parametric form as
F(x,y,z) = x/a + y/b +z/c - 1 = 0
Where a, b, c are the intercepts on the x, y, z axes, and take a = 3, b = 4, c = 5. The stress tensor at that point, in contracted notation, is σ1 = 100, σ2 = 10, σ3 = -20, σ4 = 1, σ5 = 2, σ6 = -5. Compute the stress vector at x = y = z = 60/47 using Cauchy's law.