II. Read the passage and answer the questions: 1. A rocket uses fuel to make power for the engine. The fuel is set on fire inside the rocket. As the fuel burns, it creates gases that have great pressure. These gases are blasted out of the rocket engines. These gases all go out the bottom of the rocket engine where it is open. They come out so fast and with so much power that the rocket is pushed up. It is pushed up so hard that the rocket overcomes the force of gravity, which tries to keep everything on the ground. The force that pushes up against the front of the rocket is called thrust. Unlike an airplane, a rocket does not use wings to help it fly. It just uses the power and force created by the burning fuel to make enough thrust. Questions: 1. Where is the fuel set on fire? 2. How do the gases come out to make the rocket be pushed up? . 3. What does the force of gravity try to do? . 4. What is thrust? 5. What does an airplane use to help it fly? .