Approximately, how far is the Earth's ozone layer from its surface?

More Questions:

What was the fabled city of gold that some 16th century Europeans believed existed in South America?

What sporting event is also called "birling"?

Wanamaker's of Philadelphia first US store to install what in 1878?

What painter's mental state is revealed in 750 letters he wrote to his brother Theo?

What novel won Alice Walker a Pulitzer Prize in 1983?

Which sea separates Greece from Asia Minor?

Gingivitis is inflammation of the what?

What is the condition resulting from prolonged muscular or mental activity?

What disease grounded astronaut Ken Mattingly from Apollo 13?

What is an uncastrated, adult male horse called?

What duo starred in the 1969 movie "Butch Cassidy and the Sundance Kid"?

Who plays Jen Lindley on the TV show "Dawson's creek"?

What international award did President Theodore Roosevelt win in 1906?

What was Queen Victoria's first name?

The "Bodansky Unit", now an obsolete unit, used to measure the concentration of what in the blood stream?