let's use engineering notation for the sake of brevity.
1 trillion is 1,000,000,000,000, or just 1E12, twelve zeros.
1 million is then 1E6, six zeros.
we know the discharge for one day is 3E12 gallons, and that'd do just fine for country A for 5 months. How many gallons in 1 month only?

if there are 200million inhabitants in A, namely 200E6 or 2E8 inhabitants, how many gallons per inhabitant from all those 6E11 gallons?

Answer:
Adding the variables
Step-by-step explanation:
Answer:
All except from point E's y-coordinate (which is -1.5 (found it through the equation y=-1.5 and trying to see if these coordinates are solutions to the above equation) All the others are integers, which you can find through aligning the point on the axis of the chosen (y or x) coordinate.
Step-by-step explanation:
Point C has -2 x-coordinate since it is on the x=-2 line
Similarly, point D has -2 y coordinate,
point E has 2 x-coordinate and -1,5 y-coordinate
and point F , since it's the two axis' common point has coordinates of (0,0).
Hope I helped! Further explanation can be given on request on your behalf.
I beleive it would be 5,2 but I'm not too sure