Crude oil prices slipped off the $102 per barrel plateau Tuesday morning as a consensus forecast calls for a rise in U.S. inventories for the week. The Energy Information Administration is expected to peg inventories as higher for the sixth consecutive week, as winter winds down and refineries enter the annual maintenance season. On the New York Mercantile Exchange, crude oil gave up 86 cents to $101.9177 per barrel. Natural gas gave up 11 cents to $5.37 per million British thermal units. Reformulated blendstock gasoline prices dropped 0.28 cents to $2.83 per gallon. Heating oil prices lost 1.15 cents to $3.0834 per gallon. At the pump, the national average price for a gallon of unleaded rose from Monday's $3.419 per gallon to $3.426, the AAA Daily Fuel Gauge Report said.