Game Lab - Variables

Choose all of the blocks that create a new variable in Game Lab.

• 
• 
• 
• 

Answer explanation

To create a variable, the JavaScript keyword var should be present. Otherwise, you are attempting to use an existing variable.

Every block in Game Lab represents a piece of Javascript code.

• True

• False

Answer explanation

When you use blocks in Game Lab, you are really dragging around pieces of Javascript code.

What is the final value of x when this program runs?

• 3

• 4

• 0

• Nothing. An error will occur.

Answer explanation

This is valid code. x will have the same value as y because of the last code block.

What should be changed about this code?

• Nothing. It is the best way to write this code.

• The blocks should be reordered.

• The variable names don't match.

• You must always set a variable to equal a number.

Answer explanation

The blocks should be reordered so that x is defined before it is used in other blocks.

A variable should be declared with the var keyword before it is used elsewhere.

Note: Due to how Javascript works, this code will run either way. But, it is best practice to reorder these blocks.

Which statement is most accurate about this code?

• The program will not run.

• The ellipse is very wide.

• The ellipse is at the right.

• The ellipse is at the left

• The ellipse is very tall.

Answer explanation

The correct code should have been to put width in the 3rd spot.

But, it will still work as is. The "x" value of the ellipse will be 400. This moves it to the far right.

What is wrong with this code?

• x has been declared more than once using var.

• Values should not exceed 100.

• Nothing. It is perfectly fine as is.

Answer explanation

The correct code should look like this.

You should only declare the same variable one time using the var keyword.

Note: This won't show an error in Game Lab, but it isn't correct.