For the Fe-C microstructures A, B and C in the image below, the hardest is * 1 point A B A B C Martensite FeC in a and Fe3C The tuner of phase diagrams include * 1 point For results of tensile testing of the three materials A, B and C, the material with the lowest ductility is * 1 point 300 250 200 150 100 Engineering Stress OOO B 50 0 B C 0 0.025 0.05 0.075 0.1 0.125 0.15 0.175 0.2 Engineering Strain