By Claudia Assis
SAN FRANCISCO (MarketWatch) -- Crude-oil futures on Friday ended a see-sawing session with an advance, holding on to gains despite U.S. stock weakness and a rising dollar. Crude for January delivery CL2F +1.20% added 60 cents, or 0.6%, to end at $96.77 a barrel on the New York Mercantile Exchange. Natural gas futures advanced, but heating oil and gasoline futures ended lower.
