Answer:
0.04
I rounded to one significant figures.
N=8
If you set 2/3 equal to n/12 then you multiple 3 by 4 to get 12. So you have to multiple 2 by 4 to get N.
The additive inverse of a number is just the opposite of the given number. For example; 2 and the additive inverse is -2.
If we apply this to the number we are given, we get 19.57
Best of Luck!