Observation

Many candidates attempted this question and their performance was fairly good. In part (a) (i) many candidates were able to name the types of water in the diagrams labelled A, B and C.   In part (a) (ii) they did well in it. In part (a) (iii) In part many of them failed to state disadvantages of the type of water in C if there is need for construction.  (b) they did well in it. In part (c) most of the candidates could not correctly mention stages that the water in the diagram labelled C should undergo before use.
The expected answers are as follow:

     NAMES OF TYPES OF WATER IN DIAGRAM LABELLED A, B AND C
A -       borehole                                        
B -       well water                                     
C -       tap/pipe borne                                

(ii)       ADVANTAGES OF THE TYPE OF WATER IN DIAGRAM C

            -           very potable/ hygienic/safe
-           not easily contaminated
-           its operation does not require energy during fetching

(iii)     DISADVANTAGES OF DIAGRAM C IF THERE IS NEED FOR CONSTRUCTION

• very expensive
• cost of maintenance is very high
• source of water to be used is scarce

 (b)      WAY IN WHICH THE DIAGRAM LABELLED B COULD BE CONTAMINATED
-           improper closure of the lid
-           dumping of dirts
-           indiscriminate use of containers used for drawing water/contamination by     
users      
while fetching water

•       contamination from a close by sewage         

                                                             
(c)       STAGES WATER IN THE DIAGRAM LABELLED C SHOULD UNDERGO
BEFORE USE
-           flocculation/coagulation
-           storage
-           filtration
-           pumping
-           chlorination