In 1968, what became a required part of the automobile's safety equipment in the US?

More Questions:

The adjective "callipygian" refers to someone who has a beautiful what?

What children's book character was introduced by Hans and Margret Rey in 1941?

In which US state is the geographic center of the 48 contiguous states?

What is the highest point in the United States?

Ljubljana is the capital of which European country?

Who is typically credited with the discovery of X-rays?

What element of the periodic table is named for a Jewish woman?

What is the study of inland waters called?

Tom Petty's video for his song "Don't Come Around Here No More" was inspired by what story?

In the 1994 movie "Jumanji', a stampede is released, what is the last animal to appear?

In the TV show "The Simpsons', Groundskeeper Willie comes from what country?

Roman Polanski directed which 1974 film starring Jack Nicholson?

Which character did Nick Nolte play in the 1982 film "48 Hrs."?

By what name is El-Hajj Malik El-Shabazz better known?

Who did "Time" magazine choose as its Person of the Century in 1999?