In this task, you're given an open-domain question. Your task is to provide an answer to the given question. There is only one unique answer for each question. Your answer should be short, and refer to an entity, date, number, etc. Do not put your answer in the context of a sentence.

Ex Input:
When did united last win the champions league?

Ex Output:
21 May 2008


Ex Input:
Where does the tree of life come from?

Ex Output:
many of the world's mythologies, religious and philosophical traditions


Ex Input:
How old do you have to be to buy a handgun in iowa?

Ex Output:

21