But it is notoriously ill-suited to high-tech industries that have to tailor each item to a customer's specific needs (as in a data-switching centre or air-traffic-control system) or in which it is crucial that thousands of interrelated components all work correctly together (as in a rocket vehicle).

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The line-item veto permits the president to block specific spending measures without rejecting an entire piece of legislation.

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And these consumers often visit a retail store like Wal-Mart to find the specific item they want, then search online to find the site with the best price.

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One involves the player's character walking into a specific building, picking up an item, walking out - and then returning to find a new item has appeared.

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