Answer the following with the aid of a neat, labelled figure.
a. (i) Starting from the origin O, describe step-by-step how you would locate the point representing 5 on the number line by using only an unmarked ruler and a compass.
b. (ii) Justify geometrically that the point obtained in part (i) is exactly 5 units from O.
c. (iii) Verify your result in part (ii) algebraically without using a calculator.