Lavatory cisterns are normally made of ________________?
		A. Expanded polystyrene
B. Saturated polyester
C. Perspex
D. PVC
		A. Expanded polystyrene
B. Saturated polyester
C. Perspex
D. PVC
		A. Not used for surface coating
B. A good abrasive
C. An elastomer
D. A polyester
		A. Thiokol (a polysulphide rubber)
B. Butyl rubber
C. Neoprene
D. Polyurethane rubber
		A. Improving the stretchability
B. Dyeing/colouring
C. Detergent solution washing
D. Glycol soaking
		A. Protect rubber goods from attack by oxygen & ozone present in the atmosphere
B. Reduce its viscosity to permit easier processing
C. Reduce the time of vulcanisation and quantity of vulcanising agent
D. Increase its viscosity
		A. 85
B. 135
C. 165
D. 205
		A. Its cross-linked structure
B. Its linear chain structure
C. The presence of chlorine atoms in its monomer
D. The absence of chlorine atoms in its monomer