You can fit 15 2cm in a 600mm by 500mm.
Divide 4 by 1/3, and you get the answer.
4/(1/3) = 12 servings
Domain: [-4, ∞)
Range: (-∞, 0]
*Domain are all x-values listed. Here you can see the graph going the right (positive) of -4 (Doesn't go to the left)
*Range are all y-values listed. Here you can see the graph starts from zero and goes down (negative)
Hope it helps!