You are given a list of queries separated by new line. Your job is to answer with the query that is the most well-formed or well-structured query in terms of grammar, punctuations, or spelling errors.
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Question: What is planet Earths best known feature ?
Who discovered fluoride ?
What is the most hardest division problem in the world ?
2 types of business communications enhanced by desktop publishing are ?

Answer: Who discovered fluoride ?


Question: What is the value of a 1942-D nickle worth ?
How can you forget your ex-crush ?
How much do the butt injections coast ?
When and where was Miceal Phelps born ?

Answer: How can you forget your ex-crush ?


Question: What are the different side effects medrol ?
Who invented the lightning rod and what year ?
How did sulfur got its symbol ?
How much of Canada 's land mass ?

Answer:
Who invented the lightning rod and what year ?