Chapter 2 checkpoint questions

Question 1

What is a software requirement?

Answer 1

A single function that the program must perform in order to satisfy the customer

Question 2

What is an algorithm?

Answer 2

A set of well-defined logical steps that must be taken to perform a task

Question 3

What is pseudocode?

Answer 3

An informal language that has no syntax rules and is not meant to be compiled or executed. Instead, programmers use pseudocode to create models, or “mock-ups”, of programs.

Question 4

What is a flowchart?

Answer 4

A diagram that graphically depicts the steps that take place in a program

Question 5

What does the oval symbol mean in a flowchart?

Answer 5

Ovals are terminal symbols.

Question 6

What does the parallellogram symbol mean in a flowchart?

Answer 6

Parallellograms are either output or input symbols.

Question 7

What does the rectangle symbol mean in a flowchart?

Answer 7

Rectangles are processing symbols.

Question 8

Write a statement that displays your name

Answer 8

print(“The name”)

Question 9

Write a statement that displays the following text:

Python’s the best!

Answer 9

print(“Python’s the best!”)

Question 10

Write a statement that displays the following text:

The cat said “meow.”

Answer 10

print(‘The cat said “meow.”’)

Question 11

What is a variable?

Answer 11

A name that references a value in the computer’s memory.

Question 12

Which of the following are illegal variable names in Python, and why?

x
99bottles
july2009
theSalesFigureForFiscalYear
r&d
grade_report

Answer 12

99bottles is illegal because it begins with a number.

r&d is illegal because the & character is not allowed.

Question 13

Is the variable name Sales the same as sales? Why or why not?

Answer 13

No, variable names are case sensitive.

Question 14

Is the following assignment statement valid or invalid? If it is invalid, why?

72 = amount

Answer 14

It is invalid, the variable that is receiving the assignment (in this case ‘amount’) must appear on the left side of the = operator.

Question 15

What will the following code display?

val = 99
print(‘The value is’, ‘val’)

Answer 15

The value is val

Question 16

Look at the following assignment statements:

value1 = 99
value2 = 45.9
value3 = 7.0
value4 = 7
value5 = 'abc'

After these statements execute, what is the Python data type of the values referenced by each variable?

Answer 16

value1: int.
value2: float
value3: float
value4: int.
value5: str

Question 17

What will be displayed by the following program?

my_value = 99
my_value = 0
print(my_value)

Answer 17

0

Question 18

What value will be assigned to “result” after the following statement executes?

result = 9 // 2

Answer 18

4

(The floor division operator, also referred to as integer division operator. The resultant value is a whole integer, though the result’s type is not necessarily int.)

Question 19

What value will be assigned to “result” after the following statement executes?

result = 9 % 2

Answer 19

1

The Modulus operator returns the decimal part (remainder) of the quotient.

Question 20

How do you suppress the print function’s ending newline?

Answer 20

If you don’t want the print function to start a new line of output when it finishes displaying its output, you can pass the special argument “ end = ‘’ “ to the function.

Question 21

How can you change the character that is automatically displayed between multiple items that are passed to the print function?

Answer 21

You can pass the argument “ sep= “ to the print function, specifying the desired character.

Question 22

What is the ‘\n’ escape character?

Answer 22

It is the newline escape character.

Question 23

What does the + operator do when it is used with two strings?

Answer 23

It is the string concatenation operator, which joins two strings together.

Question 24

What does the statement print(format(65.4321, ‘2f’) display?

Answer 24

65.43

Question 25

What does the statement print(format(987654.129, ‘2f’) display?

Answer 25

978,654.13

Question 26

What are three advantages of using named constants?

Answer 26

1. Named constants make programs more self-explanatory.
2. Widespread changes can easily be made to the program
3. They help to prevent the typographical errors that are common when using magic numbers.

Question 27

Write a Python statement that defines a named constant for a 10 percent discount.

Answer 27

variableName = 0.1