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Submitted on: 21 December 2011.
Revised on: 22 January 2012.
Accepted on: 09 February 2012.
___________________Independent Journal of Teaching and Learning
Submitted on: 14 August 2019.
Revised on: 12 October 2019.
Accepted on: 22 October 2019.
___________________Independent Journal of Teaching and Learning
Submitted on: 22 October 2007.
Revised on: 12 February 2008.
Accepted on: 12 March 2008.
___________________Independent Journal of Teaching and Learning