In FCC, the location of the largest interstitial site, colled octahedral, is indicated by the diagram below. (a) On what family of planes are the octahedral sites located (b) How many such sites exist in the FCC unit cell? What are the point coordinates for each of the interstitial sites? (c) How many (whole) impurity atoms per unit cell could potentially occupy the cell's octahedral sites? (d) What is the coordination number for an impurity atom occupying the octahedral site? (e) What size impurity atom could fit there (without straining the lattice) if the host were sodium