The natural challenge-response we all have in us is what will be the biggest help to the new amputees.

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Finally, the BP spill has presented an unprecedented challenge as an emergency environmental response and a long-term restoration effort.

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Caldwell was red carded following a 56th-minute challenge on Manchester City striker Carlos Tevez when the score was 0-0, provoking an angry response from Martinez, who believed his player should never have been sent off.

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In response to this challenge, London and New York City have endorsed ambitious long-term energy planning policies.

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The Archbishop of Canterbury the Most Reverend Justin Welby, who has in the past praised the quality of same-sex relationships, sees the Church's response to the issue as a challenge.

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Boeing (nyse: BA - news - people ) has continued to upgrade its 747 in response to the Airbus challenge and with a slight twist brought out its smaller 787 Dreamliner aircraft with an increased fuel-saving design.

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Indeed if Mr Blair wants a re-run, Ms Prague said she would like to speak to him again to challenge him further on his response.

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