Y = x/4
x = 4y
domain = {4(28), 4(30), 4(32), 4(34), 4(36)} = {112, 120, 128, 136, 144}
hookes law gives the equation F=kx where F is the elastic force and k is the constant and x or small e is extension if we draw a graph you'll see that the graph increases by the same ratio every single time hence giving a straight line show that they are F and x are propotional to a certain limit