General JS Questions

What does this instruction do?

var pixel = [127, 200, 19];

• Sets the color of a pixel

• Creates a variable called pixel and assigns an array of 3 values to that variable

• Reads the value of a pixel from an image

• Nothing, there's an error in it

What does this code do?

pixel = image.getPixel(120,33);

• Gets the pixel at coordinates x=120 y=33, from the image and stores it in a variable

• Modifies a pixel to have the values Red = 120 and Green = 33

• Generates an error since the word "pixel" does not have the word "var" before it.

• Prints the value of a pixel on the screen

What does this command do?

z = z - 12;

• Adds 12 to the value of z and stores the new value in z

• Subtracts 12 from the value of z and stores the new value in z

• Checks if the value of z is greater than 12

• Generates an error because z cannot be a variable name

What will be the result of running this code:

• Print all the numbers from 0 to 370 each on a separate line

• Print all the odd numbers from 0 to 370 each on a separate line

• Print all the even numbers from 0 to 370 each on a separate line

• Print all the numbers from 0 to 370 each on the same line

What will be the result of running the code on the left be?

• Print the numbers 0 to 99 on separate lines

• Print the numbers 0 to 99, each on a separate line

• Print the numbers from 0 to 99 backwards, on separate lines.

• Print the numbers 0 to 99, ten at a time, moving to the next line after each 10 numbers

Answer explanation

Can you think of a way to make the numbers in the first row line up with the numbers below them?

What's wrong with this code?

(assume that the url is correct)

• Nothing, it'll display the image

• The coordinates are wrong, they need to be 0, 0

• the word "WebImage" is incorrect. Should be Image

• There's a different error.

Answer explanation

Be prepared to discuss this one!

This code is part of a students effort to modify an image. What does it look like the student is trying to do?

• Brighten the image

• Darken the image

• Hide an image in another image

• Something else

This code is part of a students effort to modify an image. Will this code work?

• Yes, it's perfect

• No, there's one error

• No there are several errors.

An IPv4 Internet address looks like which of the following?

• FE33:1332:6E13:FFE2:FC00:DF17:7E8B:889A

• 192.168.1.1

• 275.22.36.130

• None of these

An IPv6 Internet address looks like which of the following?

• FE33:1332:6E13:FFE2:FC00:DF17:7E8B:889A

• 192.168.1.1

• 275.22.36.130

• None of these