Explore variables using the env and the set commands. • Create a new variable named hrs_worked. Assign hrs_worked a value of 20. • Create a new variable named hrly_rate. Assign hrly_rate a value of 38. • Create another variable named pay and assign it the value of hrs_worked times hrly rate. • export all 3 variables. • Set hrly rate to readonly. Try to unset hrly rate. • Use the echo command to see the values of all 3 variables • TO HAND IN: Take a screen shot of these commands for PART 1. PART 2: Experiment with creating aliases to make your use of UNIX a little easier: • Create 3 aliases using the alias command to make useful shortcut commands. • unalias one of those assignments. • TO HAND IN: Take a screen shot of these alias assignments plus their execution for PART 2

Jenna updated her status on a social network regarding her upcoming vacation. what information should jenna not provide when updating her status on a social networking site? a. her favorite quote b. her likes in popular culture c. her routine d. her opinions on social issues res

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 events"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.

Acetylene is a gas which burns rapidly on its own, and is considered highly explosive. a) true b) false