Crude oil prices rebounded Thursday after falling to less than $85 a barrel on concerns about economic growth in Europe and Asia, analysts said. Crude oil for August delivery was up $1.90, or 2.3 percent, to $85.81 a barrel on the New York Mercantile Exchange. The U.S. Energy Information Administration\'s oil inventory report shows U.S. oil inventories dropped by 4.7 million barrels, which was much more than anticipated, analysts said. The report showed a drop in gasoline demand. Reformulated blendstock gasoline was up 2.2 cents $2.77 a gallon. Home heating oil was up 4.2 cents to $2.76 a gallon. Natural gas for August delivery was up 2.1 cents, or 0.7 percent, to settle at $2.874 per million British thermal units. At the pump, the national average price of unleaded gasoline was up slightly to $3.384 per gallon Wednesday, AAA said.