Explanation

The atomic number was discovered by Henry Moseley in 1910.

Henry Moseley was an English physicist.

Explanation

Eratosthenes, the ancient Greek scholar is called the 'father of geography'.

He was the first one to use the word geography.

He also had a small-scale notion of the planet that helped him to determine the circumference of the earth.

Explanation

On 21 July 1921, a young surgeon named Frederick Banting and his assistant Charles Best

On 11 January 1922, insulin was first used in the treatment of diabetes

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Explanation

Eratosthenes was the first person to calculate the Earth's radius in the 3rd century B.C.E.

He was a Greek astronomer who lived in Alexandria, Egypt.

Eratosthenes's calculation of the Earth's radius was 6,366 km, which is close to the modern value of 6,378 km.

Explanation

Explanation

Karl Marx was a German philosopher during the 19th century.

Born on 5 May 1818, Trier, Prussia, German Confederation

Died in 1883  (aged 64) in London, England

Burial place: The Tomb of Karl Marx, Highgate Cemetery

Explanation

In the early 1950s, the first successful vaccine was created by US physician Jonas Salk.

Salk tested his experimental killed-virus vaccine on himself and his family in 1953

First used Salk vaccine in 1955 ( in activated)

while 

A live attenuated (weakened) oral polio vaccine developed by Dr. Albert Sabin and first used in 1961.

Israel launched a polio vaccine drive after 1988 in April 2022

Explanation

Sherpa Tenzing: Nepali mountaineer

Edmund Hillary: New Zealand mountaineer

All about Mount Everest

Mount Everest is the Highest peak in the world.

Explanation

Braille education system was introduced by Braille for Blinds.

Braille education system Creator: Louis Braille

Explanation

Ferdinand Magellan was the first man to sail round the world.

Ferdinand Magellan was a Portuguese explorer.