instruction:
In this task, you're given a sentence and question. Based on the information provided in a given sentence, you should identify the shortest continuous text span from the sentence that serves as an answer to the given question. Answer the question using coreference resolution. Coreference resolution is the task of clustering mentions in text that refer to the same underlying real world entities. For example let's take a sentence 'I voted for Obama because he was most aligned with my values, she said.' Here in this example 'I', 'my', and 'she' belong to the same cluster and 'Obama' and 'he' belong to the same cluster. Now let's discuss another example , original sentence: 'I voted for Trump because he was most aligned with my values',John said. Now here is the same sentence with resolved coreferences: 'John voted for Trump because Trump was most aligned with John's values',John said. 
question:
Sentence: Joe saw his brother skiing on TV last night but the fool didn't have a coat on Question: Who is the fool?
answer:
brother


question:
Sentence: In July, Kamtchatka declared war on Yakutsk. Since Yakutsk's army was much better equipped and ten times larger, they were defeated within weeks. Question: Who was defeated
answer:
Kamchatka


question:
Sentence: I put the cake away in the refrigerator. It has a lot of butter in it. Question: What has a lot of butter?
answer:

cake