Grateful acknowledgement is made to the following sources:


Resource 3: Heart rate: Original source: Wikipedia [Tip: hold Ctrl and click a link to open it in a new tab. (Hide tip)] (Accessed 2008)

Resource 5: Space and measure: Original source: (Accessed 2008)

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.

Resource 5: Space and measure

Section 2: Measuring and handling time