Answer the questions given below.
(i) Define the nth root of a positive real number.
(ii) Show that 13 is an irrational number.
(iii) Describe, step by step, how you would construct and mark the point representing 13 on a horizontal number line beginning at O(0).
(iv) Give a brief mathematical reason, using the Pythagoras theorem, to justify that the point obtained in part (iii) is indeed at a distance 13 units from O.