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\*.

what episode does angelina leave in season 2
10

malware that essentially is a form of social engineering
Trojan horses

when did the world population hit 7 billion

October 2017