AP CS A Unit 7 Quiz PRACTICE

When instantiating a new ArrayList, which data types can we use? Select all that apply:

• int

• Integer

• String

• Double

• double

Consider the following code segment.

What is printed as a result of running this code segment?

• [1, 2, 3, 4]

• [2, 0, 3, 4]

• [2, 3, 4]

• [1, 3, 4]

• [1, 0, 3, 4]

Suppose the following line is used to replace /* Missing Code */.

System.out.println(list.get(0));

What is printed as a result of executing the code segment?

• hotdog costs $2.0

• soda costs $0.0

• water costs $1.0

• none costs $0.0

• hotdog costs $2

Suppose the following line is used to replace /* Missing Code */. System.out.println(list.get(list.size()-1)); What is printed as a result of executing the code segment?

• water costs $1.0

• water costs $1

• hamburger costs $3.5

• none costs $0.0

• There is an error that occurs because we are trying to access an index out of range

Suppose the following lines are used to replace /* Missing Code */. list.remove(1);

System.out.println(list.get(1)); What is printed as a result of executing the code segment?

• soda costs $-3.0

• soda costs $0.0

• hotdog costs $2

• hotdog costs $2.0

• water costs $1.0

After running the code, what is the size of bulbs?

• 2

• 3

• 4

• 5

• 6

Consider the following method that is intended to test if all the Strings in the ArrayList start with a lowercase letter.

Which of the following could replace /* Missing Code */ so that the method works as intended? (You may assume all strings in the ArrayList begin with a letter character.)

• I only

• II only

• III only

• II and III

• I, II, and III

Which of the following could correctly replace /* Missing Code */ so that removeNumbers works as intended?

• 
• 
• 
• 
• None of the above

Consider the following method.

Which of the following is printed as a result of executing the following statement?

System.out.println(sequence(5));

• It is an empty list because the for loop never runs

• [5, 10, 15, 20, 25]

• [6, 11, 16, 21]

• [6, 11, 16, 21, 26]

• [1, 6, 11, 16, 21]

Consider the following method.

Which of the following describes what the method mystery() does to the ArrayList words?

• The ArrayList words is always left unchanged.

• The ArrayList words is extended to twice its size by repeating the first element of the list at the end of the original list until the size of the list is twice the original size.

• The ArrayList words is extended to two times its size by repeating all elements in the list.

• The ArrayList words is extended to two times its size by replacing each single element in the list with that element repeated two times.

• The method generates an IndexOutOfBoundsException.