Across
- 2. a device used for sending and receiving radio signals
- 4. a connection or link between people that allows them to share information is a ................system
- 5. spacecraft that travel around Earth and receive signals that can be sent back to a different place on Earth
- 7. a type of energy that travels through the air
- 8. the invention or improvement of tools or machines that help us perform tasks or solve problems
Down
- 1. machines that are used to send written messages through telephone lines
- 3. a device that sends signals to a distant place
- 4. something that is done in order to make money
- 6. sent out or communicated to many people – a television show is an example
- 9. systems connecting many people