What would you use a trait for? (add it in PHP 5 as well)

How can you find out which of the user's friends are also subscribed to your application?

Facebook Applications can use cross-domain scripting by submitting which variable when authenticating the auth token?

When using the friends.areFriends method, which form of data can the uid parameters be in?

If your API key is invalid you will receive the following error number from the Facebook API:

Which formats does the auth.createToken method support when returning data?

Finished applications that have been submitted show up in...

What is a Post-Add Url?

Which formats does the auth.createToken method support when returning data?

If your API key is invalid you will receive the following error number from the Facebook API:

When using the friends.areFriends method, which form of data can the uid parameters be in?