How many wheels are there on the trailer of an "18-wheeler" truck?

More Questions:

Of the 88 keys on a piano, how many are black?

When first published, what was the original intent of the "Michelin Guide"?

What is traditionally the main fruit ingredient in a rickey?

Which Lord of the Rings character has an alter ego called "Gollum"?

On what thoroughfare does the Muffin Man live?

What's the world's largest predatory fish?

What bird, also known as a Man O'War, can glide for hours without flapping its wings?

Which TV show features a character nicknamed Sweet Dee?

In what film did a character named Pumpkin rob a restaurant while Vincent Vega was dining nearby?

What movie sees Elvis Presley sent to the slammer for manslaughter?

What is the name of the detective in the Steve Miller hit "Take the Money and Run"?

What video made stars of the overall-clad "Sal" and "Harv"?

What European capital was first dubbed the City of Light in the 19th century?

What famous trials were held in 1692 and 1693?

What operation brought over 1,500 German scientists, engineers and technicians following the end of World War II to the US to aid in military research?