Answer:
B) PO2
Step-by-step explanation:
first solve empirical formula
 50%of P and 50%of O
-  divide each by molecular mass
 P. O
 50/32. 50/16
 1.5. 3.0
- divide both by the smallest
 1.5/1.5. 3.0/1.5
 1. :. 2
 Empirical formula=PO2
 
Molecular formula=PO2
 (PO2)n= 64
 (32+(16×2)=64
 (32+32)n=64
 64n=64
 n= 1