Poison ivy and poison oak are easily recognizable by their groups of three leaves.

Douglas MacArthur's father's name was Arthur MacArthur.

You should swim parallel to the shore rather than away from it.

Chiang Kai-shek was leader of China during World War II.

After World War II, the countries China, Great Britain, the Soviet Union, and the United States were known as the Big Four.

The area of a circle is found by using the formula Pi x radius².

Germany's attack on Poland started World War II.

The emperor of Japan before World War II was Hirohito.

Charged atoms are called ions.

The Panama Canal was opened in 1914.

Combustion is the chemical process that occurs when a substance reacts rapidly with oxygen.

Those Christians who believe in the fundamental truths of Christianity are know as Fundamentalists.

Robert Boyle laid the foundations for chemistry.

Theodore Roosevelt was the United States of America's 26th President.

Oxygen, hydrogen, nitrogen, neon, krypton, and argon are all noble gases, gases which do not usually combine with other elements.

Silicon is a semimetal element that is used to make computer chips.

Mercury is the only metal that is liquid at room temperature.

A carbon atom has six protons, six neutrons, and six electrons.

Osmium is the densest element.

Garrett A. Morgan invented the traffic light.