Within a small chamber, an internal combustion engine combines a precisely measured mix of fuel (typically petrol or diesel) and air. Once ignited, this explosive combination causes an expansion of hot, pressurized gases to exit the chamber, typically via pistons or a turbine. Thus the chemical energy is converted, albeit often not very efficiently, into mechanical energy which can then be used to power motors and drive machines.
The Declaration of Independence was the document which told the British that the colonies were separating and forming a new nation. The correct answer is A.
