Many candidates were able to:

-Sketch a two-bay metal glazed sliding window;
-Define the term geometrical stair;
-List materials used for stair construction.

However, some candidates failed to:

-Label the sketch of a two-bay metal glazed sliding windows;
-State the difference between a riser and a tread in relation to stair construction.

Expected response to question 3 is as given below:

 

(b)(i) Geometrical Stair is a stair constructed with treads that are tapered on plan and which are arranged around a center support.
(ii) Materials for stair construction
Stone, timber, reinforced concrete, steel and aluminium.

(c)Riser is the vertical member connecting two successive treads whilst tread is the horizontal member connecting two successive risers.