After a big drop last week, gas prices in Maine are back on the rise. Price-monitoring website MaineGasPrices.com reports Monday that the average retail price of gasoline in Maine has risen just over a penny in the past week to an average of $3.95. Nationally, prices are going in the other direction. The national average that has fallen more than two cents per gallon in the last week to $3.79 per gallon. Maine prices are now 42 cents per gallon higher than the same day one year ago and more than six cents per gallon higher than a month ago.