Final answer:
A web administrator is responsible for maintaining and securing the web server, ensuring its correct operation, and troubleshooting issues related to the web server.
Step-by-step explanation:
The duties of a web administrator primarily include maintaining and securing the web server, along with troubleshooting the web server when issues arise. This role involves tasks such as updating server software, monitoring server performance, implementing security measures, and ensuring that web applications are operating correctly.
While the other duties listed such as connecting devices on a network, maintaining firewalls and databases are related to IT, they specifically pertain to network administrators, security specialists, and database administrators respectively. The web administrator is focused on the websites and the underlying infrastructure that supports them.