Which of the following terms is used to describe a program that copies itself repeatedly, using up resources and possibly shutting down the computer or network?
(a) a virus
(b) a warm
(c) a trojan horse
(d) a rootkit

Some of your friends have gotten into the burgeoning field of time-series data mining, in which one looks for patterns in sequences of events that occur over time. purchases at stock exchanges--what’s being bought-- are one source of data with a natural ordering in time. given a long sequence s of such events, your friends want an efficient way to detect certain "patterns" in them--for example, they may want to know if the four events buy yahoo, buy ebay, buy yahoo, buy oracle occur in this sequence s, in order but not necessarily consecutively. they begin with a collection of possible events (e.g., the possible’ transactions) and a sequence s of n of these events. a given event may occur multiple times in s (e.g., yahoo stock may be bought many times in a single sequence s). we will say that a sequence s’ is a subsequence of s if there is a way to delete certain of the events from s so that the remaining events, in order, are equal to the sequence s’. so, for example, the sequence of four events above is a subsequence of the sequence buy amazon, buy yahoo, buy ebay, buy yahoo, buy yahoo, buy oracle their goal is to be able to dream up short sequences and quickly detect whether they are subsequences of s. so this is the problem they pose to you: give an algorithm that takes two sequences of even~s--s’ of length m and s of length n, each possibly containing an event more than once--and decides in time o(m n) whether s’ is a subsequence of s

Chloe is building a kiosk-based excel application. she wants to make some modifications to the screen elements in order to keep users from being distracted by parts of the application that are irrelevant to her application. she turns to henry for guidance as she knows he built a similar solution earlier this year.chloe has decided to hide the worksheet gridlines and the vertical scroll bar. what does henry tell her to use to do this? a) screen elements dialog boxb) display options dialog boxc) customization dialog boxd) excel options dialog box

Communication is the exchange of information. true false