3. For a carbon fiber reinforced epoxy composite with Gf = 110 GPa and Gm = 1.4 GPa, plot the compressive failure strength as a function of volume fraction from V = 0.2 - 0.9 for three different imperfection angles of = 1,2 and 3. Take the shear yield strength to be T12+ = 50 MPa. Assume that plastic microbuckling will be the dominant failure mechanism. (15 points)