How is volume calculated directly and indirectly

Directly: volume is calculated via the length times width times height formula
Indirectly: volume is the space something takes up, so typically the water displacement method would be suitable to calculate the amount of volume in an object that can't be calculated directly

The answer is b.the gaseous state is electrically positive, while the plasma state is electrically negative. 

Make them both to where they have the denominator of 18that makes 3/2 equal 27/18 and 1/9 equal 2/18so now you have  27/18x+5=2/18subtract 5 from the other sideso now you have 27/18x+2/18-5then subtract 2/18 from 27/18 to get 25/18x=-5then divide 25/18 by -5 and your answer will be  -5/18