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\*.

[Q]: when was it discovered that lead was poisonous
[A]: at least 2000 BC


[Q]: when was the system of checks and balances created
[A]: 1748


[Q]: who played john brown in the blue and the gray
[A]:
Sterling Hayden