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 were air brakes first used on trucks

A: the early 20th century
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Q: who led the metis in the rebellions at red river in 1870 and in the northwest in 1885

A: Louis Riel
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Q: who does leif garrett play in the outsiders

A:
Robert "Bob" Sheldon
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