Carbon atoms have a surface proportionality constant, D0, of 2105m2/s and an activation energy of 142kJ/mol. Most nearly, what is the diffusivity of carbon in face-centered cubic ( (FCC) gamma-iron at 1000C ? (A) 2.981011m2/s (B) 8.551011m2/s (C) 5.23106m2/s (D) 1.28104m2/s