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\*.
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Question: the shortest distance between two points on the earth's surface is

Answer: great-circle distance


Question: who is first in line for king of england

Answer: Charles, Prince of Wales


Question: when did the go pro hero 6 come out

Answer:
September 28, 2017