Disk is the ability to spread data over multiple disks or volumes

Suppose there is a relation r(a, b, c) with a b+-tree index with search keys (a, b).1. what is the worst-case cost of finding records satisfying 10 < a < 50 using this index, in terms of the number of records n1, retrieved and the height h of the tree? 2. what is the worst-case cost of finding records satisfying 10 < a < 50 and 5 < b < 10 using this index, in terms of the number of records n2 that satisfy this selection, as well as n1 and h defined above? 3. under what conditions on n1 and n2, would the index be an efficient way of finding records satisfying the condition from part (2)?

This chapter lists many ways in which becoming computer literate is beneficial. think about what your life will be like once you’re started in your career. what areas of computing will be most important for you to understand? how would an understanding of computer hardware and software you in working from home, working with groups in other countries and contributing your talents.

Auser is given read permission to a file stored on an ntfs-formatted volume. the file is then copied to a folder on the same ntfs-formatted volume where the user has been given full control permission for that folder. when the user logs on to the computer holding the file and accesses its new location via a drive letter, what is the user's effective permission to the file? a. read b. full control c. no access d. modify e. none of the above