Answer:
A balance
Explanation:
Scientists measure mass with a balance, such as a triple beam balance or electronic balance. In science, the volume of a liquid might be measured with a graduated cylinder.
For counting x you use simple equation for the distance covered by the object when it moves with constant velocity:

that gives you 20m after 1st second, 40 m after 2nd second, 60 m after 3rd second and so on.
For counting y you have to use the equation for the distanced covered by the object moving with constantly accelerating velocity (symbols refering to vertical movement):

that gives you 5m after 1st second, 20m afters 2nd second, 45m after 3rd second and so on.
Add minus signs before y positions to receive graph presenting the movement of the ball.
So the points are: P1=[20,-5], P2=[40,-20], P3=[60,-45] and so on... Pn=[x,y].
The guys before me was almost right. But instead of it being vertical it is horizontal.