just answer these ccna questions from the internet

THis is the area where you will post weely about the topics posted.

1) Explain why basic security measures are necessary on network devices? Name two basic security measures.

2) What are security vulnerabilities? List three of them. Explain what an “actor” is in network security.

3) What commands can you use to acquire information about the devices in a network?

4) List two troubleshooting commands to test connectivity of a route.