Also . . .

Delta Air Lines Inc. started charging a minimum fee of $2 on round-trip tickets for U.S. flights not purchased through its Internet site, to pay for rising ticket-distribution costs.

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American Financial Group Inc., a property and casualty insurer, said it agreed to buy auto insurer Worldwide Insurance Co. from Aegon of the Netherlands for $115 million in cash.

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Enron Oil & Gas Co., a unit of Enron Corp., said it hired Goldman, Sachs & Co. as its financial advisor as the company faces possible buyout negotiations with an unnamed suitor.