is a software utility program designed to protect a system from internal attacks from viruses, trojan hourse, spyware

works in background and steals sensitive data

trojans can self replicate

Someone using your presonal information to open accounts,file texes or make purchases

software created to gather snsitive indormation or gain access to private computer systems

How many pairs of letters from the English alphabet are possible?

A .................... of n different elements is an ordering of the elements such that one element is first, one is second, one is third and so on.

One important application of the Fundamental Counting Principle is in determining the number of ways that n elements can be arranged (in order).

A club has nine members.
• In how many ways can a president, vice president, and secretary be chosen from the members of this club?

How many permutations of {a, b, c, d} that are ended with c ?

A random experiment is a process whose outcome is certain

The set of all possible outcomes of experiment :

P ( E ) ∈

P ( S ) =