Seafloor spreading at midoceanic ridges is how scientists first discovered the periodic reversal of what?

More Questions:

In which Mega Man game can you acquire the Gemini Laser?

Handel's "Largo" comes from which opera?

What does "Lo Stivale', the local name for the Italian peninsula, mean in Italian?

Which six states share a border with Idaho?

Phnom Penh is the capital of which Asian country?

What bay does the San Mateo bridge cross?

What country did the Venetian blinds originate in?

What breed of cat is tailless?

What is the name for the tiny blood vessels that branch off from arteries and veins?

The cecum is part of which intestine?

What is a male witch called?

What is one of pi's rational approximations?

What is the main food of the Oystercatcher?

For which movie did director John Schlesinger receive an Oscar in 1970?

What was the name of the B-29 bomber that dropped an atomic bomb on the city of Nagasaki during WWII?