Ahypothetical ax type of ceramic material is known to have a density of 3.75 g/cm3 and a unit cell of cubic symmetry with a cell edge length of 0.61 nm. the atomic weights of the a and x elements are 90.5 and 37.3 g/mol, respectively. on the basis of this information, which one of the following crystal structures is possible for this material? sodium chloride cesium chloride zinc blende