Proportionality between mass and volume.

The question:

The volume of a sphere is directly proportional to its radius cubed. The mass of a spherical steel ball is directly proportional to its volume, as ρ = m/v. Sketch a graph showing how the mass of a spherical stable ball varies with its radius cubed.

The solution I tired doing:
m = ρV
m = ρ( $\frac{4}{3} πr ³$ )
I'm quite not sure if I should give the spherical ball a random density and then chart it out. I'm also quite confused on what values or labels should put on the x-axis and the y-aixs.

Hi!
The question says: "...how the mass of a spherical stable ball varies with its radius cubed".

So the mass should be on the y-axis and the radius cubed on the x-axis.

You have $m = (ρ \cdot \frac{4}{3} π) \cdot r^{3}$ where $ρ \cdot \frac{4}{3} π$ is constant.

Yes, you should select a value for the density (for example 7850 kg/m³ for steel) to create the diagram.

Svara