Grateful acknowledgement is made to the following sources:
Photographs and images
Resource 1 : A careful look at the torch bulb: Adapted from Umthamo 3, University of Fort Hare Distance Education Project
Resource 3 : Lighting a bulb – templates and discussion: Adapted from Umthamo 3, University of Fort Hare Distance Education Project
Electric bell:(Accessed 2008)
Eight feared electrocuted in Imo,from Charles Ogugbuaja, Owerri: Adapted from The Guardian, http://www.guardiannewsngr.com/ news/ article17/ 230107 (Accessed 19/06/07)
Every effort has been made to contact copyright holders. If any have been inadvertently overlooked the publishers will be pleased to make the necessary arrangements at the first opportunity.