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\*.

Input: Consider Input: when was the dubai metro green line opened to public

Output: September 2011 (


Input: Consider Input: why is the congo river not navigable for its entire course

Output: the three major falls


Input: Consider Input: who played the father in eight is enough


Output: Dick Van Patten