RICHMOND, Va. (AP) _ Virginia motorists are continuing to enjoy a drop in gasoline prices. AAA Mid-Atlantic says the average price for a gallon of gasoline was $2.81 on Tuesday. That’s 1 cent less per gallon compared to the previous week and 33 cents less compared with the same week a year ago. Average prices range from $2.70 per gallon in Richmond to $2.88 in Charlottesville. Motorists in the Norfolk area are paying on average $2.85 per gallon. The average price in Roanoke is $2.79. Nationally, gas prices average $3.03 this week.