2 Chapter 1 Introduction to Computers, the Internet and Visual C# Visual C# How to Program 6th Edition Solution Manual Self-Review Exercises 1.1 Fill in the blanks in each of the following statements: a) Computers process data under the control of sequences of instructions called . ANS: computer programs. b) A computer consists of various devices referred to as , such as the keyboard, screen, mouse, hard disks, memory, DVD drives and processing units . ANS: hardware. c) Data items processed by computers form a(n) that becomes larger and more complex in structure as we progress from the simplest data items (called “bits”) to richer data items, such as characters, fields, and so on. ANS: data hierarchy. d) Computers can directly understand only their language, which is composed only of 1s and 0s. ANS: machine. e) The three types of computer programming languages discussed in the chapter are ma- chine languages, and . ANS: assembly languages, high -level languages. f) Programs that translate high -level -language programs into machine language are called . ANS: compilers. g) A(n) processor implements several processors on a single “microchip” —a dual -core processor has two CPUs and a quad -core processor has four CPUs. ANS: multicore. h) Windows 10 introduced the for building Windows apps that run on desktop computers, notebook computers, tablets, phones, Xbox and even Microsoft’s new HoloLens augmented reality holographic headset —all using nearly identical code. ANS: Universal Windows Platform (UWP). 1.2 Fill in the blanks in each of the following statements: a) Objects, or more precisely the that objects come from, are essentially reusable software components. ANS: classes. b) You send messages to an object. Each message is implemented as a method that tells a method of the object to perform its task. ANS: call. c) A new class of objects can be created quickly and conveniently by ; the new class absorbs the characteristics of an existing class, possibly customizing them and add - ing unique characteristics of its own. ANS: inheritance. d) To create the best solutions, you should follow a detailed analysis process for determin - ing your project’s (i.e., defining what the system is supposed to do) and de- veloping a design that satisfies them (i.e., deciding how the system should do it). ANS: requirements. e) Visual C# is driven. You’ll write programs that respond to mouse clicks, key - strokes, timer expirations and touches and finger swipes. ANS: event. f) A key goal of Java is to be able to write programs that will run on a great variety of com - puter systems and computer -control devices. This is sometimes called . ANS: write once, run anywhere. 1.3 Fill in the blanks in each of the following statements: Self-Review Exercises 3 a) The executes .NET programs. ANS: Common Language Runtime (CLR) of the .NET Framework. b) The CLR provides various services to code, such as integrating software com- ponents written in different .NET languages, error handling between such components, enhanced security and more. ANS: managed. c) The ability of a program to run without modification across multiple platforms is known as platform . ANS: independence. d) Visual Studio is a(n) in which C# programs are developed. ANS: IDE. e) You can sell your own Windows Phone apps in the . ANS: Windows Store. 1.4 State whether each of the following is true or false . If false , explain why. a) Software objects model both abstract and real-world things. ANS: True. b) The most popular database model is the relational database in which data is stored in simple tables . A table includes records and fields . ANS: True. c) A database is a collection of data that’s organized for easy access and manipulation. ANS: True. d) Secondary storage data takes much longer to access than data in primary memory, but the cost per unit of secondary storage is much higher than that of primary memory. ANS: False: The cost per unit of secondary storage is much lower than that of primary memory. e) High -level languages allow you to write instructions that look almost like everyday Eng- lish and contain commonly used mathematical expressions. ANS: True. f) An object has attributes that it carries along as it’s used in a program. ANS: True. g) The Transmission Control Protocol (TCP) ensures that messages, consisting of sequen - tially numbered pieces called bytes, were properly routed from sender to receiver, ar - rived intact and were assembled in the correct order ANS: False. The pieces are called packets, not bytes. h) The information -carrying capacity of communications lines on the Internet has in- creased tremendously, while hardware costs have increased. ANS: False. Hardware costs have decreased. i) You can build web -based apps with C# and Microsoft’s ASP.NET technology. ANS: True. j) Java has become the key programming language for the Mac OS X desktop operating system and all iOS-based devices, such as iPods, iPhones and iPads. ANS: False. The language is Swift, not Java. k) Microsoft’s ASP.WEB technology is used to create web apps. ANS: False. It’s ASP.NET technology. l) Microsoft’s Windows operating system is the most widely used desktop operating sys - tem worldwide. ANS: True. 1.5 Arrange these byte measurements in order from smallest to largest: terabyte, megabyte, petabyte, gigabyte and kilobyte. ANS: kilobyte, megabyte, gigabyte, terabyte, petabyte. 4 Chapter 1 Introduction to Computers, the Internet and Visual C# 1.6 Describe the two -step translation process for preparing your C# code to execute on your particular computer. ANS: C# code is first compiled into MSIL and placed in an executable file. When the app executes, another compiler called the JIT (just -in-time) compiler in the CLR trans - lates the MSIL in the executable file into machine -language code (for a particular platform). Exercises 1.7 Fill in the blanks in each of the following statements: a) The programs that run on a computer are referred to as . ANS: software b) Systems such as smartphones, appliances, game controllers, cable set-top boxes and au- tomobiles that contain small computers are called . ANS: embedded systems c) Just as characters are composed of bits, are composed of characters or bytes. ANS: fields d) Information on secondary storage devices is ; it’s preserved even when the computer’s power is turned off. ANS: persistent e) Translator programs called convert high -level language code into machine - language code . ANS: compilers f) In object -oriented programming languages, we create a program unit called a(n) to house the set of methods that perform its tasks. ANS: class g) Use a building -block approach to creating your programs. Avoid reinventing the wheel —use existing pieces wherever possible. Such software is a key benefit of object -oriented programming. ANS: reuse 1.8 Fill in the blanks in each of the following statements: a) Although many different OOAD processes exist, a single graphical language for com - municating the results of any OOAD process has come into wide use. This language, known as the , is now the most widely used graphical scheme for modeling ob- ject-oriented systems. ANS: UML b) Tim Berners -Lee developed the for sharing information via “hyperlinked” text documents on the web. ANS: HyperText Markup Language (HTML) c) The CLR is a(n) machine. It is software that manages the execution of pro- grams and hides from them the underlying operating system and hardware. ANS: virtual d) Converting a program to run on a different platform from which it was originally in- tended is called . ANS: porting. e) Microsoft’s Windows is a cloud -computing platform that allows you to de- velop, manage and distribute your apps in the cloud. ANS: Azure. (Instructor Note: "Microsoft’s Windows" should be simply "Microsoft" in this exercise.) Exercises 5 f) By using existing controls —which are objects —you can create powerful apps much faster than if you had to write all the code yourself. This is a key benefit of software . ANS: reuse 1.9 State whether each of the following is true or false . If false , explain why. a) The smallest data item in a computer can assume the value 1 or the value 2. Such a data item is called a bit (short for “binary digit” —a digit that can assume either of two val- ues). ANS: False. Such items have the value 0 or 1. b) The Unicode character set is a popular subset of ASCII that represents uppercase and lowercase letters, digits and some common special characters. ANS: False. ASCII is a subset of Unicode. c) Each of the following is a form of computer output: data displayed on screens, printed on paper, played as audio or video on PCs and media players, used to control other de- vices, such as robots, 3D printers and “intelligent” appliances. ANS: True. d) Reuse helps you build more reliable and effective systems, because existing classes and components often have gone through extensive testing, debugging and performance tuning. ANS: True. e) One of the W3C’s primary goals is to make the web universally accessible to everyone regardless of disabilities, language or culture. ANS: True. f) C# is available only on Microsoft Windows. ANS: False. There are ports of C# for other platforms, such as Linux. g) The .NET Framework Class Library has millions of valuable prebuilt classes that have been tested and tuned to maximize performance. ANS: False. Thousands, not millions, of prebuilt classes. h) .NET programs can run on any platform. ANS: False. .NET prorgrams run on the Common Language Runtime, which is a virtual machine. i) The Universal Windows Platform (UWP) is designed to provide a common platform (the underlying system on which apps run) and user experience across all of your devices including personal computers, smartphones, tablets and Xbox Live. ANS: True. 1.10 What is a key advantage of interpreters over compilers? What is a key disadvantage? ANS: A key advantage is that interpreters can execute high -level language programs directly (without the need for compilation). A key disadvantage is that interpreted programs exexute more slowly than compiled programs. 1.11 What is the key advantage of using the new async feature in preference to using old -style multithreading? ANS: The new features simplify asynchronous programming, because the compiler hides much of the associated complexity from the developer. 1.12 What are operating systems? ANS: Operating systems are software systems that make using computers more convenient for users, app developers and system administrators. They provide services that allow each app to execute safely, efficiently and concurrently (i.e., in parallel) with other apps.
