1. Maths, Science and Technology Education Department, Central University of Technology, 20 President Brand Street, Bloemfontein 9300, Free State, South Africa
2. Department of Physics, University of South Africa, 28 Pioneer Ave., Florida Park 1709, Gauteng, South Africa
3. School of Computing, University of South Africa, 28 Pioneer Ave., Florida Park 1709, Gauteng, South Africa