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Groups of depositors in front of the closed American Union Bank, New York City. April 26, 1932. Great Depression run on bank crowd

Causes of the Great Depression

The Judiciary Committee of the U.S. House of Representatives receiving a deputation of female suffragists, January 11, 1871, a lady delegate (identified as Victoria Woodhull) reading her argument (cont'd)

Who Was the First Woman to Run for President of the United States?

Vietnam War. U.S. President Lyndon B. Johnson awards the Distinguished Service Cross to First Lieutenant Marty A. Hammer, during a visit to military personnel, Cam Ranh Bay, South Vietnam, October 26, 1966. President Johnson

Vietnam War Timeline

The impeachment trial of Pres. Andrew Johnson, illustration from Frank Leslie's Illustrated Newspaper, March 28, 1868.

What If the President Is Impeached?

Scolex (head) of the tapeworm Taenia solium. The hooks of the scolex enable the tapeworm to attach to the intestinal wall.

Uninvited Guests: The 7 Worst Parasitic Worms

Bristlecone pine (Pinus Longaeva) on the slope of Mount Washington in Great Basin National Park in the Nevada desert.

How Can Some Trees Survive for Thousands of Years?

Dr. Martin Luther King Jr. addresses marchers during his "I Have a Dream" speech at the Lincoln Memorial in Washington. August 28th 1963

Was Martin Luther King, Jr., a Republican or a Democrat?

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microscopy

Learn about this topic in these articles:

compound microscopes

In microscope: Mechanical components
…usually mounted on a glass slide. Routine microscope slides were fixed at 3 × 1 inches during the Victorian era and are still produced at the metric equivalent of those dimensions (7.5 × 2.5 cm) today. The specimen, usually immersed in a material with an R.I. that matches that of…
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