E: 08/08 Win a copy of Code Green - Experiences of a Lifetime{MERGED}

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Lonely Planet - Code Green
Win a copy of Code Green - Experiences of a Lifetime, the new guide to greener travel from the experts at Lonely Planet.
We have five copies of this title to give away - simply answer the question below! Plus, click here for some great advice on making your holiday more environmentally friendly coupled with other great releases from Lonely Planet.

Question:

The measure of the impact that human activities have on the environment is otherwise known as:

• Carbon handprint
• Carbon footprint:j
• Carbon fingerprint