Oil prices rose above $80 a barrel Monday in Asia, extending a three-week rally, the Associated Press reported. Benchmark crude for March delivery was up 51 cents to $80.32 a barrel at late afternoon Singapore time in electronic trading on the New York Mercantile Exchange. The contract added 75 cents to settle at $79.81 a barrel on Friday. In other Nymex trading in March contracts, heating oil rose 1.92 cents to $2.089 a gallon, and gasoline gained 2 cents to $2.105 a gallon. Natural gas dropped 8.4 cents to $4.96 per 1,000 cubic feet. In London, Brent crude was up 61 cents at $78.79 on the ICE futures exchange.