Acknowledgements

Except for third party materials and otherwise stated (see terms and conditions [Tip: hold Ctrl and click a link to open it in a new tab. (Hide tip)] ), this content is made available under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 Licence

Course image: FoodCraftLab in Flickr made available under Creative Commons Attribution-ShareAlike 2.0 Licence.

Grateful acknowledgement is made to the following sources for permission to reproduce material in this course:

Cartoons (Sections 1.4, 1.5, 2.1 and 3.5): copyright © S. Harris

Cartoon (Section 3.4): CartoonStock.com © Dan Rosandich

Mars orbiter: NASA

All other written material contained within this course originated at the Open University

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