,Solution jand jAnswer jGuide jFor jAll jChapters: jLambert, jFundamentals jof jPython: jFirst jPrograms, j3e, jCY24, j9780357881019; jChapter j1, jIntroduction
Chapters
LAMBERT, FUNDAMENTALS OF PYTHON: FIRST PROGRAMS, 3E, CY24, 9780357881019; CHAPTER 1,
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INTRODUCTION
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TABLE OF CONTENTS J J
Exercise Solutions ........................................................................................................................................ 1
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Exercise 1.1................................................................................................................................................ 1
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Exercise 1.2................................................................................................................................................ 2
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Exercise 1.3................................................................................................................................................ 3
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Review Questions Answers.......................................................................................................................... 4
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Programming Exercises Solutions .............................................................................................................. 8
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Debugging Exercises Solutions ................................................................................................................... 8
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EXERCISE SOLUTIONS J
EXERCISE 1.1 J
1. List three common types of computing agents.
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Solution:
Human beings, desktop computers, cell phones
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2. Write an algorithm that describes the second part of the process of making change (counting out the coins
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and bills).
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Solution:
There are various ways to do this, but here is one:
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Repeat
Select the largest unit of money that is less than or equal to the remaining change
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Subtract this unit from the remaining change
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Until the remaining change is 0
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The collection of units selected represent the change
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3. Write an algorithm that describes a common task, such as baking a cake.
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,Solution jand jAnswer jGuide jFor jAll jChapters: jLambert, jFundamentals jof jPython: jFirst jPrograms, j3e, jCY24, j9780357881019; jChapter j1, jIntroduction
Solution:
There are various ways to do this, but here is one:
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Preheat an oven to 375 degrees j j j j j
Add 1 cup of water and 1 egg to a mixing bowl
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Beat the liquid mixture in the bowl until the ingredients are blended Add
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the contents of a boxed cake mix to the mixing bowl
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Beat the mixture in the bowl until the ingredients are blended
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Pour the contents of the mixing bowl into a lightly greased cake pan
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Bake the cake in the oven for 45 minutes
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4. Describe an instruction that is not well defined and thus could not be included as a step in an algorithm.
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Give an example of such an instruction.
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Solution:
Attempting to divide a number by 0 j j j j j j
5. In what sense is a laptop computer a general-purpose problem-solving machine?
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Solution:
A laptop computer is a general-purpose problem-solving machine because it is programmable and can solve
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any problem for which there is an algorithm.
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6. List four devices that use computers and describe the information that they process. (Hint: Think of the
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inputs and outputs of the devices.)
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Solution:
Digital camera—images, music player—sound, cell phone—text, ATM—numbers
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EXERCISE 1.2 J
1. List two examples of input devices and two examples of output devices.
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Solution:
Input devices—keyboard and mouse, output devices—monitor and speakers
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2. What does the central processing unit (CPU) do?
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Solution:
The CPU fetches, decodes, and executes instructions.
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3. How is information represented in hardware memory?
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Solution:
Information is represented using binary notation, which in hardware is a pattern of voltage levels.
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, Solution jand jAnswer jGuide jFor jAll jChapters: jLambert, jFundamentals jof jPython: jFirst jPrograms, j3e, jCY24, j9780357881019; jChapter j1, jIntroduction
4. What is the difference between a terminal-based interface and a graphical user interface?
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Solution:
A terminal-based interface supports only the input and output of text with a keyboard and monitor. A
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graphical user interface supports the output of images and the manipulation of them with a pointing device,
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the mouse.
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5. What role do translators play in the programming process?
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Solution:
A translator converts a program written in a high-level language (human readable and writable) to an
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equivalent program in a low-level language (machine readable and executable).
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EXERCISE 1.3 J
1. Describe what happens when the programmer enters the string "Greetings!" in the Python shell.
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Solution:
Python reads the string "Greetings!", evaluates it, and displays this string (including single quotes) in
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the shell.
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2. Write a line of code that prompts the user for their name and saves the user’s input in a variable called
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name.
Solution:
name= input("Enter your name: ")
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3. What is a Python script?
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Solution:
A Python script is a complete Python program that can be run from a computer’s operating system.
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4. Explain what goes on behind the scenes when your computer runs a Python program.
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Solution:
If the program has not already been translated, Python’s compiler translates it to byte code. The Python
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virtual machine then executes this code.
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