P = 33 kN, a = 42 cm, b = 57 cm,
E1 = 13 * 10^4 N/cm^2, E2 = 8 * 10^4 N/cm^2, (τ = G * γ)
(v = 0.5), γ1 = 1, γ2 = 1, c = 2 cm
1) Find the critical loading for the first column.
2) Determine the thickness "d" so that the second column is subjected to the same loading.