help please

2. What is an Ethernet card?

3. What does a network switch do?

4. What is a bandwidth?

5. What do you need to have a dial-up connection to the internet?

6. How is a DSL interconnection different from telephone modem connection?

7. What impacts does frame relay have on a metropolitan area network?

8. What is a cat 5 cable used for?

9. What is a Bluetooth?

10. What does a Wi-Fi do?

11. How does a VPN protect confidentiality?

12. What are the four principles of computer security?