"Ali has always been an optimistic and outgoing person, " the source close to the family said, adding that the young man loves photography, movies, cars and motorcycles.

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Ms Mitchell said her mother was an outgoing person.

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If a manager leaves, the total cost of hiring a replacement (the head-hunter fees, the premium required to entice him and the time it takes him to settle into his job) is usually several times the outgoing person's salary.

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But, said Mr Reichert, the outgoing president has "protected more special places in the sea than any other person in history".

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