To solve this problem, we need to understand the structure of an FCC (Face-Centered Cubic) lattice and the location of octahedral voids.$\\$In an FCC unit cell:$\\$• Atoms are located at each of the eight corners and at the center of each face.$\\$Octahedral voids in an FCC structure:$\\$• There is one octahedral void at the center of the unit cell.$\\$• There are 12 octahedral voids at the edge centers of the unit cell.$\\$Each edge-centered octahedral void is shared by four adjacent unit cells.