Crude oil prices held above $91 per barrel Friday morning with the commodity up about 50 cents on the week. The death of Venezuelan leader Hugo Chavez has given traders pause. Venezuela has the largest accessible oil reserves in the world. Instability in the country could provoke a supply-scare that would boost prices. On the New York Mercantile Exchange, West Texas Intermediate crude oil settled down overnight, dropping 15 cents to $91.21 per barrel. Gasoline added 2.12 cents to $3.1502 a gallon. Home heating oil shed 1.13 cents to reach $2.9613 a gallon. Natural gas added 1.7 cents to hit $3.59 per million British thermal units. At the pump, the national average price for a gallon of regular unleaded gasoline dropped from Thursday\'s $3.719 per gallon to $3.712, the AAA Daily Fuel Gauge Report said.