The price of gasoline has shot up again.Ward Lenz of the Iowa Department of Natural Resources says there was a 17-cent-per-gallon increase in gas prices over the past month. That ties for the second largest increase ever in the state. The average price for a gallon of gas was a dollar fifty-six a gallon.Lenz says prices could go up even more.Lenz says prices shot up for one main reason, an increase in crude oil prices.The highest month-to-month increase in gas prices was from March to April of this year when prices jumped 34-cents-per-gallon.