How do you calculate rate of expansion of gas with temperature with a gradient of the line being 0.2?

Question

i am doing a graph plotting in volume and temperature it has asked: How do you calculate rate of expansion of gas with temperature with a gradient of the line being 0.2? 

Answer 1

Let R(T) be the rate of expansion of the gas as a function of temperature T.  The given information translates into

 

R(T) = 0.2T,

 

assuming T and R are expressed in certain units.  The wording of the question tells you that the rate of expansion is proportional to temperature, and that the constant of proportionality is 0.2, in some system of units.