A synthetic full backup is a type of backup that combines a full backup with one or more incremental backups to create a new full backup without accessing the source data. This type of backup is suitable for database servers, as it reduces the backup window, minimizes the impact on the server performance, and provides faster recovery time. Verified Reference: [Synthetic Full Backup]

A SAN (Storage Area Network) is a network of storage devices that can provide shared storage capacity to multiple servers. By connecting the server to a SAN, the administrator can increase the storage capacity of the server without adding any internal disks or expansion cards. This solution can be implemented quickly and without any downtime. Verified Reference: [What is a SAN and how does it differ from NAS?]

Explanation
The cache is a temporary storage area that holds frequently accessed data or instructions for faster retrieval. The cache can improve the read times for accessing files by reducing the need to access the hard drive, which is slower than the cache memory1. Therefore, the first step the technician should take is to check if the cache is turned on for the new file server. If the cache is turned off, the technician should enable it and see if the read times improve. The other options are incorrect because they are not the first steps to take.
Adding more memory, installing faster hard drives, or enabling link aggregation are possible ways to improve the performance of the file server, but they are more costly and time-consuming than checking the cache.
Moreover, they may not address the root cause of the problem if the cache is turned off.

Explanation
The first action that the administrator should take before swapping out the GPU card inside a server is to shut down the server. This is to ensure that the server is not running any processes that might be using the GPU card, and to prevent any damage to the hardware or data loss due to sudden power loss. Shutting down the server also reduces the risk of electrostatic discharge (ESD) that might harm the components. Reference:
https://pcgearhead.com/installing-a-new-gpu/