(-3)^2 = 9
-3^2 = -9
Hope this helps!
Similarities: same atomic number
Differences: they have a different number of neutrons
So first you do 3,816 divided by 12 , because you need to find how much for 1 so then you can find out 25% off of 1. To check your work put down 318 times 12 to prove that you're right. Which would be 318 times 25 = 79.5. If you use a calculator it won't have the decimals ( if you just do the numbers ), but the rest is above.
