What is permanently-frozen subsoil called?

More Questions:

In what decade did the Vatican withdraw their requirement that Catholics refrain from eating meat on Fridays?

Which two boxing weight classifications are named for animals?

'Songbird" is a book about what jazz singer's remarkable posthumous career?

How many US states border Ohio?

A benzene ring is made up of atoms of what element?

Which element of the periodic table is named after a titan of Greek myth?

In the movie "Speed', dropping below what speed will blow up the bus?

Gregory Peck played Lt. Joe Clemons in what 1950s film?

Who played Malcom in the TV show "Malcom in the Middle"?

What is the name of the apartment complex the Jetsons live in?

What movie was the first US movie to have a soundtrack album?

For what 2005 film did George Clooney win a Best Supporting Actor Oscar?

What does legend say started the great Chicago fire of 1871?

Who played the male lead role in the film "Avatar"?

What is the most densely populated US state?