big idea 3

The variable age is to be used to represent a person’s age, in years. Which of the following is the most appropriate data type for age ?

• Boolean

• string

• number

• list

The variable isOpen is to be used to indicate whether or not a store is currently open. Which of the following is the most appropriate data type for isOpen ?

• number

• boolean

• list

• string

A teacher is writing a code segment that will use variables to represent a student’s name and whether or not the student is currently absent. Which of the following variables are most appropriate for the code segment?

• A string variable named s and a Boolean variable named a

• A string variable named s and a numeric variable named n

• A string variable named studentName and a Boolean variable named isAbsent

• A string variable named studentName and a numeric variable named numAbsences

Consider the following code segment.

What is the value of r as a result of executing the code segment?

• 20

• 10

• 30

• 40

Consider the following code segment.

What are the values of first and second as a result of executing the code segment?

• The value of first is false, and the value of second is false.

• The value of first is false, and the value of second is true.

• The value of first is true, and the value of second is false.

• The value of first is true, and the value of second is true.

Consider the following code segment.

x ← 25

y ← 50

z ← 75

x ← y

y ← z

z ← x

Which of the variables have the value 50 after executing the code segment?

• x only

• y only

• x and z only

• x, y, and z

Which of the following is a benefit of using a list as a data abstraction in a program?

• Lists often allow their size to be easily updated to hold as many data values as needed.

• Lists convert all elements to strings so that they can be inspected character-by-character.

• Lists prevent duplicate data values from appearing in the list.

• Lists are used to store all input data so that there is a running record of all user input.

A programmer has a need to round many numeric values to the nearest integer. Which of the following best explains the benefit of using a list as a data abstraction in this situation?

• Keeping the numeric values in a list makes it easier to apply the same computation to every data element.

• Keeping the numeric values in a list makes it easier to round a number to the nearest integer.

• Keeping the numeric values in a list makes it easier to prevent a program from unintentionally changing the value of a variable.

• Keeping the numeric values in a list makes it easier to prevent a program from attempting to access an index beyond the length of the list.

Assume that both lists and strings are indexed starting with index 1.

The list wordList has the following contents.

["abc", "def", "ghi", "jkl"]

Let myWord be the element at index 3 of wordList. Let myChar be the character at index 2 of myWord. What is the value of myChar ?

• "e"

• "f"

• "h"

• "i"

Consider the following code segment.

What are the contents of yourList after the code segment is executed?

• [20, 40, 60, 80, 10, 30, 50, 70]

• [10, 30, 50, 70]

• [20, 40, 60, 80]

• [10, 30, 50, 70, 20, 40, 60, 80]