After a 27-hour heat treatment at 1000°c (and subsequent cooling to room temperature), the concentration of a is 3.8 wt% at the 14.4-mm position within metal b. if another heat treatment is conducted on an identical diffusion couple, this time at 880°c for 27 hours, at what position will the composition be 3.8 wt% a? the preexponential and activation energy values for the diffusion of a in b are 3.7 × 10-6 m2/s and 152 kj/mol, respectively. x = enter your answer in accordance to the question statement mm