In this task, you're given an open-domain question. Your task is to provide an answer to the given question. There is only one unique answer for each question. Your answer should be short, and refer to an entity, date, number, etc. Do not put your answer in the context of a sentence.

What time frame does stranger things take place?
1980s

Who plays alex von strucker in agents of shield?
Spencer Treat Clark

What type of goods were traded on the columbian exchange?

human populations