If you have a speech to give, a test to take or an important meeting, for example, some anxiety will help you focus on the event and make sure you're prepared for it, Barlow said.

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Each one is hoping that the event will help launch their products on the world market with delegates set to include vehicles manufacturers, specialist suppliers, technology companies and fleet operators.

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Last month, they held an event on the White House lawn to help rally support for the Olympic bid.

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