What is the advantage of using keys in a database? Keys
records of one table with the others.

Laire writes a letter to her grandmother, in which she describes an amusement park she visited last week. she adds pictures of that place in her letter. which feature of a word processing program will claire to remove unwanted parts of the pictures?

Local area networks use many of the same network technologies and the internet, only on a smaller scale. devices that access lans are equipped with a network interface that contains circuitry for wireless or wired connections. devices also have a physical address, in addition to the ip addresses acquired from a dhcp server. the most popular wired technology is . the most popular wireless technology is , which can be configured as a(n) or star topology. setting up a lan and configuring its router is fairly easy. the first step is to change the standard to one that is secure. next, create a(n) that uniquely identifies the network by name. it is also important to activate wireless to prevent wireless signals from being intercepted during transmission. a limited-access network can be created for visitors to use. by activating , the router will be able to assign ip addresses to each device that joins the network. to connect to a secure lan that is protected by encryption, an encryption , or password, is required. lans can be used to access data collected by iot devices and the networks that tie these devices together. technologies such as rfid, nfc, bluetooth smart, zigbee, and z-wave offer -power links, essential for battery-powered devices that can’t expend excess amounts of energy transmitting data.

Write a program to analyze student’s scores. each student’s id and 4 original test scores are saved in the attached file “student_id_scores.txt”. assume there are exactly 15 students in the class.• the program first opens the file, reads student’s ids and scores from the file and saves them in two arrays: o create a one-dimensional string array “ids” to store the student’s ids.o create a (parallel) two-dimensional int array “scores” to store student’s original test scores. this array has 5 columns, the original 4 test scores should be saved in the first 4 columns, and the last column will be used to save the average score after the calculation in next step.• the program then retrieves test scores from the array “scores”, calculates average score and determines the final letter grade based on the rules in the table below for each student. assume average score is integer value.average score = (score1 + score2 + score3 + score4) / 4average score letter grade90 ~ 100 a80 ~ 89 b70 ~ 79 c60 ~ 70 d0 ~ 60 f• the average score should be saved back in the 5th column of “scores” array.• create a new parallel one-dimensional char array “grades” to save each student’s letter grade.• program also needs to find the number of a, number of b, number of c, number of d and number of f grade. as well as the highest, lowest and average score of the class.• finally, program will display all of the original scores and all results on the computer screen using the format shown as the sample output below.• the program must contain at least the following functions: (1) a function “getscores” to read and store data into “ids” and “scores” arrays.(2) a function “analyzescores” to calculate student’s average score, determine letter grade, get the number of a, b, c, d and f, find the highest, lowest and average score of the class.(3) a function “displayresults” to display all of the results