Crude oil prices gave up 53 cents Monday to $98.79 per barrel on the New York Mercantile Exchange. Reformulated gasoline blendstock for January lost 0.61 cents to $2.777 a gallon. January heating oil gave up 1.38 cents to reach $3.0643 a gallon while natural gas gained 6 cents to $4.47 per million British thermal units. The national average price of unleaded regular gasoline rose at the pump, climbing to $3.25 a gallon from Sunday's $3.244, the AAA Daily Fuel Gauge Report said.