For which pair of points can you use this number line to find the distance?

A number line going from negative 2 to positive 8 in increments of 1. Points are at 0 and 3.
(0, 3) and (3, 0)
(1, 0) and (–1, 3)
(2, 0) and (2, 3)
(–1, 0) and (–1, –3)

the linear relationship that represents a variation in direct proportion is the linear function that varies according to the numbers of its domain, for example the cost of producing x number of items can be represented in direct proportion by f (x) = mx + b, where m is the constant of proportionality, x the number of articles produced and b the fixed cost