Answer:
d. 10
Explanation:
The 24 means the atomic mass and twelve means the number of electrons. You subtract the number of electrons from the atomic mass. 24-12=12
Then, since there's +2, you subtract 2 from 12 which equals 10 which means there are 10 electrons now.
The confusing thing is that + means subtract and - means add here.
Hope this helps.
