Greenfoot Quiz

In the Crab game scenario, the Lobster class contained all of the code that describes how all _____'s behave.

• Lobster

• Crab

• Worm

• Actor

In the Crab scenario, how were these two images used?

• The Crab class switched between these two images to animate the legs of the crab.

• The Crab class displayed crab when the game starts and crab2 when the game ends.

• The Crab class displayed crab when a worm was eaten and crab2 when a Crab eats a Lobster.

• The Crab class displayed crab when a worm was eaten and crab2 when a Lobster eats a Crab.

Which of the following accurately describes the code shown here.

• line 15 stores the file "crab.png"

• line 16 stores the file "crab2.png"

• line 17 stores a whole number

• lines 15 and 16 store Java primitives

Which of the following best describes what the keyword "void" means?

• it denotes that the method will only execute any commands that it contains

• it creates a variable using the name that follows it

• it creates an array of values from the code that it executes

• it denotes that the method will return a value once it completes executing any commands it contains

Which of the following accurately describes the code shown here?

• The turnAtEdge() method will cause an object to turn 17 times every time it executes.

• The turnAtEdge method will cause an object to turn 17 degrees when isAtEdge() is true

• The turnAtEdge method will cause an object to turn 17 degrees when isAtEdge() is false

• The turnAtEdge() method will cause an object to turn 17 degrees every time it executes.

Which of the following is an accurate statement about the code shown here.

• if an object created from the Lobster class is touching an object of the Crab class the program will stop.

• if an object created from the Crab class is touching an object of the Worm class the program will stop.

• if an object created from the Lobster class is touching an object of the Worm class the program will stop.

• if an object created from the Lobster class is touching another object of the Lobster class the program will stop.

Which term below is illustrated in the two lines of code shown here.

• variable declaration

• class declaration

• object instantiation

• dot notation

• A Cliff object is a Mover object

• A Cloud object is a Mover object

• A Mover object is a Cliff object

• A Pengu object is a Mover object

Which of the following accurately describes the code shown here?

• the jump() method will be executed only if the call to onGround() returns false

• the jump() method will be executed only if the call to onGround() returns true

• the moveLeft() method will be executed only if the call to isKeyDown("space") returns false

• the moveLeft() method will be executed only if the call to isKeyDown("right") returns false

The under object will be null if the expression does not return any objects. Which phrase below best matches the meaning of the word null?

• nothing

• an integer value of zero

• ground objects

• negative values