Answer:
equivalent price/ gallon = 13.98 US$ / gallon
Step-by-step explanation:
Assuming that the exchange rate is 1.762 US$ /€ , then
thus
equivalent price/ gallon = liters/gallon * euros / liter * dollars/euro
equivalent price/ gallon = 3.78541178 liters/ gallon * 2.096 € /liter * 1.762 US$ /€ = 13.98 US$ / gallon
equivalent price/ gallon = 13.98 US$ / gallon
if the actual price would be different from the equivalent , then there would be an arbitrage opportunity ( profit with no risk)