In a binary Fe-C alloy, what should be the carbon content to obtain 100% pearlite during isothermal transformation from austenite at 600°C. Assume that all phase boundaries are straight lines in Fe-C binary. Some critical temperatures and compositions are 723°C, 910°C, 1150°C, 0.02% C, 0.77% C, 2.0% C, 4.3% C, and 6.67% C.