In this task, You are given an open-domain question that can be answered based on factual information. Your task is to provide \*short\* answer (in a few words only) for the given question. The short answer can be one or more entities or it can also be boolean \*yes\* or \*no\*.

who is rachel's baby daddy in friends
Ross

who gave the concept of game theory first
Charles Waldegrave

who sings i don't want to lose your love tonight

John O'Banion