Are sources of energy that most cars or trucks use to move?

• Gasoline and diesel

• water and oxygen

• Nitrogen

• Helium

Is the process of burning fuel?

• Heat

• dam

• combustion

• balloons

Is a chemical reaction that produces energy?

• combustion

• Heat

• gasoline

• diesel

In an ______________________ engine, fuel is burned outside the engine.

• Internal combustion

• External combustion

• Petrol

• Oil

___________ , ______________, and____________ are three kinds of fuel used to produce steam.

• water, soil, and the sun

• cars, helicopters, and trucks

• Coal, oil, and wood

When the burning of fuel takes place inside an engine, the engine uses _______________________

• Internal combustion

• external combustion

• gasoline

• petroleum

_____________ turbines are also used to make electricity.

• plants

• wood

• steam

• soil

The _______________________ brothers observed pieces of burning paper rise upward above fire.

• Montgolfier

• Warner brothers

• Disney

The main part of a balloon is called the ________________ .

• ball

• plastic bag

• envelope

Large, modern hot-air balloons are made of _______________

• nylon

• wood

• fabric

• metal