is an example of a set of prewritten classes that allows you to access data stored in a database.

Acomputer is a multipurpose device that accepts input, processes data, stores data, and produces output, all according to a series of stored . the processing unit of most modern computers is a(n) . the instructions that tell a computer how to carry out a task are referred to as computer , which are distributed as software. computers run three main types of software: software, system software, and development tools. an example of system software is a computer system, which is essentially the master controller for all the activities that a digital device performs. digital devices are constructed using tiny electronic components that represent data bits as electrical signals. the system unit houses the system board, which contains several circuits made from semiconducting materials. computers come in three popular form factors: component, , and slate. many of today's digital devices operate on battery power supplied by ion batteries. battery life and lifespan can be extended by following good battery management practices.

Facial expressions and gestures are examples of messages.

1. ask the user how many questions are in the quiz. 2. ask the user to enter the key (that is, the correct answers). there should be one answer for each question in the quiz, and each answer should be an integer. e. g., 34 7 13 100 81 3 9 10 321 12 might be the key for a 10-question quiz. you will need to store the key in an array. 3. ask the user to enter the answers for the quiz to be graded. there needs to be one answer for each question. note that these answers do not need to be stored; each answer can simply be compared to the key as it is entered. 4. when the user has entered all of the answers to be graded, print the number correct and the percent correct. 5. add a loop so that the user can grade any number of quizzes with a single key. after the results have been printed for each quiz, ask "grade another quiz? (y/n)." note: you only have one array (the key). you are not creating a new key for each set of quiz answers.