instruction:
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.
question:
Eight furlongs are equal to what standard length?
answer:
1 mile


question:
Who presides over any impeachment trial of the president of the united states?
answer:
Chief Justice of the United States


question:
What adds a phosphate group to adp to form atp?
answer:

ATP synthase