Explanation:

The DL20 Gen10 Plus is a flexible and affordable 15" deep server supporting the latest Intel XEON E processors12.

The DL180 Gen10 is a secure and cost effective IP 2U server delivering flexible storage capacity, delivering a high core count, and a large memory footprint12.

The DL345 is a high-density, four-socket server with high performance, scalability and reliability, all in a 2U chassis for business-critical computing performance12.

The DL560 is a secure 2P 2U server delivering world-class compelling performance with the right balance of expandability and scalability12.

Explanation:

RAID 0: This level has zero overhead from capacity perspective, as it uses all the available disk space for data storage without any redundancy or parity. However, it also has no fault tolerance and if one disk fails, all data is lost12.

RAID 1: This level has capacity of one drive as overhead, as it uses disk mirroring to create an exact copy of data on two or more disks. This provides high reliability and fault tolerance, but reduces the usable disk space by half12.

RAID 5: This level has capacity of one drive as overhead, as it uses disk striping with parity to distribute data and parity blocks across three or more disks. This provides a balance between performance and reliability, as it can tolerate one disk failure without losing data12.

RAID 6: This level has capacity of two drives as overhead, as it uses disk striping with double parity to distribute data and two parity blocks across four or more disks. This provides higher reliability and fault tolerance than RAID 5, as it can tolerate two disk failures without losing data12.