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 				- Physical prototype, (5 marks) (2019)
 				- Analytical prototype, (5 marks) (2019)
 				- Comprehensive prototype. (5 marks) (2019)
+				- three phases of prototyping ( 2018)
+				- uses of prototypes ( 2018)
 			- ### Costs (2019) Topic 11-12
 				- Component costs, (5 marks) (2019)
 				- Support costs, (5 marks) (2019)
 				- Indirect allocations as part of Overhead costs. (5 marks) (2019)
 			- ### New products and New product development (2019, 2018)
-				- #### Booz, Allen & Hamilton (1982) Classification Scheme (2019) Topic 17
+				- ~~~#### Booz, Allen & Hamilton (1982) Classification Scheme (2019) Topic 17~~~
 					- Repositioning (4 marks) (2019)
 					- four (4) elements through which products can be differentiated (2019)
 					- the five alternatives that are open to the firm ( 2018)
 					- kinds of new products identified by Booz Allen and Hamilton ( 2018)
 					- four elements where values can be added to the basic or ‘core’ product to augment its appeal ( 2018)
-				- Product life cycle (2019) Topic 17
-				- #### prototyping ( 2018) Topic 12 - 13
-					- three phases of prototyping ( 2018)
-					- uses of prototypes ( 2018)
+				- ~~~Product life cycle (2019) Topic 17~~~
 			- ### system-level design (2019) Topic 11
 				- product architecture (2019)
 				- key characteristics of modular and integral architecture. (2019)