please help if you can. thank you.

Answer:
[tex]a. BaF_{2} \\b. SnCl_{4}\\ c.Cr_{2} O_{3} \\d. FeO\\e. Li_{3} P[/tex]
Explanation:
Hey, just for a quick tip..you can use a cross to determine which ion will have how many atoms. check the image attached.