"A meter stick is held vertically behind an object on a spring. The object vibrates from the 20cm mark to the 32cm mark on the stick. Find the displacement when the object is at the 20cm mark, 24cm mark, 26cm mark, and 30cm mark."

Question

I had found the equilibrium position to be 26cm, and the amplitude to the 6cm. However, when they ask for displacement, do they mean in reference to the equilibrium position, or where the object begins moving (20cm)?