MnO Has Either a Structure Like NaCl or a Structure

MnO has either a structure like NaCl or a structure like CsCl. The edge length of the MnO unit cell is 4.47 *10^-8 cm, and the density of MnO is 5.28 g/cm³.
A) Does MnO crystallize like NaCl or like CsCl?
B) If the ionic radius of oxygen is 140. pm, estimate the ionic radius of manganese.
C) Does the calculated ratio of the cation radius to the anion radius for MnO support your answer in part A? Explain.