Answer:
See below
Step-by-step explanation:
Part a)
Ba⁺²
Since it has a positive charge, this means it has lost electrons and that too 2 electrons. It has lost 2 electrons.
Part b)
As⁻³
Since it has a negative charge, it has gained electrons and that too 3 electrons. It has gained 3 electrons.
Part c)
Cu⁺²
It has a positive charge, so it has lost electrons and that too 2 electrons. It has lost 2 electrons.
![\rule[225]{225}{2}](https://img.qammunity.org/2023/formulas/english/college/eq413d752mwtrwwenrzwldxt4w1olmf1b3.png)