First Author:   Andrew Phiri North West University (Potchefstroom Campus) phiricandrew@yahoo.com   A. Phiri, School of Economics, North West University, Private Bag X6001, Potchefstroom, 2520, South Africa       Second Author: Peter Lusanga North West University (Potchefstroom Campus) 20878346@nwu.ac.za   Faculty of Engineering, Faculty of Engineering, Private Bag X6001, Potchefstroom, 2520, South Africa