music: what do you call a voice between a tenor & a bass?

Questions

The first city to reach a population of 1 million people was ----------, Italy in 133 B.C. London, England reached the mark in 1810 and New York City, USA made it in 1875. Today, there are over 300 cities in the world that boast a population in excess of 1 million.?

There are approximately 100,000 glaciers in --------------?

The first letter of every continent's name is the same as the last: AmericA, AntarcticA, EuropE, AsiA, --------------, AfricA.?

The geographic center of ---------- is located in the city of Thunder Bay.?

There are approximately 320,000 ------------- in the world.?