What is the basic unit of measuring storage capacity of computer?​

One of your customers wants you to build a personal server that he can use in his home. one of his concerns is making sure he has at least one backup of their data stored on the server in the event that a disk fails. you have decided to back up his data using raid. since this server is for personal use only, the customer wants to keep costs down. therefore, he would like to keep the number of drives to a minimum. which of the following raid systems would best meet the customer's specifications? a. raid 0 b. raid 1 c. raid 5 d. raid 10