Task: Question Answering
Input (English): Background Paragraph: A major use for petroleum products is fuel for cars, trucks, airplanes, trains, and other vehicles. The chemical used are usually a mixture of compounds containing several carbon atoms in a chain. When the material is ignited, a massive amount of gas is created almost instantaneously. This increase in volume will move the pistons in an internal combustion engine to provide power. A jet plane works on a similar principle. Air comes into the front of the engine and mixes with the jet fuel. This mixture is ignited and the gases formed create a lot of pressure to push the plane forward. The idea can be seen even more clearly in the case of a rocket launch. The ignition of the fuel (either solid-state or liquid) creates gases produced under great pressure that pushes the rocket up. 
Story: Gwen is driving on a highway in her old car. It's a pretty empty highway so you can hear her car engine pretty clearly. She forgot to fill up on fuel and eventually her car stops running. She has to walk to the nearest gas station and fill up a gas can to get going again. 
Question: Will the amount of pressure in the engine increase or decrease when the fuel is ignited?
Output (English): increase.