Answer 1

I have learn som functional language like Haskell, Clojure, Scala and soon Erlang.

Daytime i'am codeing i Java/C# and Python.
But i use the thinking of functional becure this often makes better and less bugg:ig code.

So if you never will work with functional language, i still a good thing to learn.

Haskell i "pure" witch is 100% functional no exceptions, so it is harder to learn but it will alos force you to do functional way solutions.

I have food a lot of this cource on Cursera and other free sites.
functional is a very diffrent way of thinking so do not give up after 1-2 tries.