Question Regarding 2015 Common App Questions

http://blog.commonapp.org/2015/03/31/2015-2016-essay-prompts/
The link provided is from the Common App website and I have a few questions regarding it.

1.) Are those questions for the 2015-2016 school Year
2.) Do i have to answer all those questions?
3.) What is the word count if I have to answer all of them

These prompt are for the 2015-16 application cycle, meaning for the senior class of 2016 that will be entering college as a freshman in the Fall of '16. There are 5 prompts to choose from. Just pick one of them. The word limit is not to exceed 650 words.