At what age did tennis player Rafael Nadal turn professional?

More Questions:

What brand of cheese celebrated its 60th birthday in 1978?

What popular show features characters named after famous artists?

Who merged with the struggling Cleveland Barons in 1978?

Alfred Jingle appears in which Dickens novel?

What two characters are sculpted on Hannibal, Missouri's Main Street?

What country is Puccini's opera, "Turandot', set in?

Phnom Penh is the capital of which Asian country?

The first atomic bomb test split an atom of what fissionable element?

Which metal has the chemical symbol "W"?

Mallard and Ruddy are species of what bird?

In 1939, Philo T. Farnsworth sold his patents for what invention to RCA Victor?

Which missionary and saint founded a monastery on the island of Iona?

When did Arizona and New Mexico become states?

Who is the founder of Carthage?

On what date did the 2016 Dyn Cyberattack take place, rendering some of the largest Internet services unusable for several hours?