Please answer the questions using the following information? The crystal structure of BX is in the structure of rock salt (rock salt). The radius of the B+2 ion is 0.096 nm, and the radius of the X-2 ion is 0.138 nm. The atomic mass of the Bion is 15 g/mol and the atomic mass of the Xion is 30 g/mol. a) Calculate the ionic packing of the BX crystal? b) Calculate the theoretical density of the BX crystal