PROVIDENCE — Gasoline prices, which have climbed steadily since winter, jumped an average of 13 cents in Rhode Island over the last week, AAA Northeast says.The average price of a gallon of regular unleaded gasoline is $2.839 at self-service pumps in Rhode Island, according to AAA's weekly survey. Since Feb. 19, the price has climbed 53 cents per gallon. A year ago, the average price was one cent lower at $2.829.Despite the increase here, Rhode Island [...]