Input question: Which element discovered by Cavendish in 1766, has a name that means 'water producing'?

Output answer: hydrogen

Input question: 5W-20, 10W-30, and 20W-20 are common weights of what commodity?

Output answer: motor oil

Input question: Who won the 2010 Open Golf Championship at St. Andrews?

Output answer: louis oosthuizen

Input question: Michael Phelps has won 22 Olympic medals, more than any other person, how many of these were Gold?

Output answer:
18