Internal friction peaks for the interstitial diffusion of carbon in tantalum were measured in a torsion experiment for two angular frequencies. For an angular frequency of 1 = 2.4 Hz maximum damping was observed at T1 = 130C and for 2 = 9.0 Hz at T2 = 150C. Tantalum is a bcc transition metal with a lattice parameter of 3.30 . a) What is the activation enthalpy of the interstitial diffusion of carbon? b) What is the diffusion coefficient of carbon at 250C? c) What is the value of the pre-exponential factor DN0?