Here are the answers to the questions I posted:
1) In which sport are the shoes made entirely of metal?
Horseracing
2) In terms of Presidential elections, what was the unique achievement of Thomas Jefferson?
He was the only sitting VP to defeat a sitting President
3) What is the origin of the term "Yankees"?
From the Dutch name Jan-Kees
4) What city in the world has the largest subway system?
Moscow
5) What percentage of people worldwide have never placed or received a telephone call?
80%