I do not understand the process of solving this question. Please help

Question

The density of copper is 8.92g/cm. If you plotted the mass of copper in grams versus the volume in cubic centimeters, what would the slope of the line be?

Answer 1

The mass of a material is proportional to its volume which means that if you have twice the volume of the same material it will weight twice heavier. If you have one cup of water and it is 1 kg, two cups of water weight 2 kg. In other word, you have the following equation connecting the two

m = d * V

in which m is mass, V is volume, and d is the proportionality constant. We also call d, density since

d = m/V

so for V =1 , we get d = m. In words, density is the mass per unit volume (V = 1).

now if you plot m versus V, you get a line and the slope of the line is d which is 8.92g/cm in your question.