How many computer languages are in use?

Which civilization developed the following: seismological detectors, matches, paper, sliding calipers and wheel borrow.

A meteor would burn up more rapidly in the atmosphere of Mars than it would passing through the Earth’s atmosphere.

The launching of which naval vessel started a race to produce turbine-powered “all-big-gun” warships?

Which two aeronautical engineers, serving opposing sides during World War II, independently invented the jet engine?

Who invented flexible photographic film?

What does fiber optic cable resemble, in terms of size?

In 1959, the U.S.S.R. launched a rocket with two of which animals aboard?

What two countries agreed to develop the Concorde jet in 1962?

Who were the first two people ever to walk on the moon?

In 2007, a three-year study concluded what about global warming?

Lithium was approved by the FDA in 1970 for the treatment of what kind of depression?

Which comet had its closest approach to Earth in 1997?