How would you set up question two?

Iron is allotropic in that it can have different crystal structures depending on temperature and pressure. For instance, at atmospheric pressure, iron adopts an FCC crystal structure between 912C1394C ( iron) and a BCC crystal structure outside this temperature range ( and iron). At high pressure, iron adopts an HCP crystal structure. Recall that most properties arise from the crystal structure and the properties can be further enhanced/tailored by various means including doping. Iron is often times doped with carbon. Carbon is favored because of its small radius (0.071nm) which allows the atom to position itself at the interstitial sites. In BCC iron, the lattice parameter is 0.2866nm and the carbon atoms enter the tetrahedral sites (e.g red point 21411 on plane (001) in Figure 1). Figure 1: BCC Tetrahedral Sites represented by unfilled circles and a red filled circle. 24 equivalent locations in total. In FCC iron, the lattice parameter is 0.3571nm and the carbon atoms enter the octahedral sites (e.g red point 212121 or point 0021 in Figure 2 ). Figure 2: FCC Octahedral Sites represented by unfilled circles and a red filled circle. 13 equivalent locations in total. (1) Would you expect a greater distortion of the crystal by an interstitial carbon atom in FCC or BCC iron? (2) What would be the atomic percentage of carbon in each type of iron if all the interstitial sites were filled? The basis for atomic percentage (at\%) is the number of moles of an element in relation to the total moles of the elements in an alloy and may be computed as follows