(a)        Part (a(i)) of the question seemed difficult to most of the candidates.  The right response expected from the candidates is:
            - the importance of carbon in steel is to enable steel to be hardened.
(b)        Most of the candidates could not give the correct answer to this part of the question also.  The correct answer is that, tempering colours are used as a guide to determine the tempering temperatures.

In (c and d), most of the candidates gave the required responses to these parts of the question.

Design principles include:

- balance;
- unity;
- harmony;
- proportion;
- rhythm;
- functions and
- emphasis.