By what elemental property is the average weight of an atom classified?

In what season do leaves begin to change color?

What medieval plague killed off so much of Europe that those left behind had higher wages and more disposable income, which they used on linen clothes, which meant an abundance of rags, dropping the cost of paper over parchment, so it became economical for German goldsmith Johann Gansfleisch, better known by his mother's name of Gutenberg, to invent printing?

What popular Chinese game is played with a set of tiles?

Who sang the famous song ”How Will I Know” (1985)?

Known for its red-light district and cannabis-selling cafes, what city's appropriate symbol is three crosses, or "xxx"?

In real life he divorced his wife in order to marry his nanny, but in Mrs Doubtfire he divorces his wife and becomes her nanny. Who?

What color can you add to another color to darken it?

In the movies, what last name is shared by Liesl, Friedrich, Brigitta, Kurt, Gretel, Marta and Luisa?

Who sang the famous song ”Valerie” (2007)?

Who sang the famous song ”With Or Without You” (1987)?

Which President appointed George C Marshall as army Chief of Staff in 1939?

What country's Founding Fathers include the 56 "Signers" and the 55 "Framers"?

In what state did President Ronald Reagan die?

Elmer and Leonard were, respectively, the "East" and "West" composers with what last name?