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Pollution is the detrimental effect of human activity on the natural environment.
The desalination process produces drinking water from seawater.
The most famous and most magnificent amphitheater of Rome was built in the 1st century.
This animation presents the formulas to calculate the perimeter and area of shapes as well as the surface area and volume of solids.
The church of the "Holy Wisdom," built in the Byzantine Empire, had been one of the largest religious buildings until 1935, when it was converted into a museum.
The ear converts the vibrations of air into electric signals which are then processed by the brain.
This animation demonstrates different types of volcanic eruptions.
The world's most famous citadel, the Acropolis of Athens was built in the 5th century B.C., during the Age of Pericles.
The round tower of the largest fort in the Arabian Peninsula had an ingenious defense system.
This animation demonstrates how the Earth and the Moon were formed.
Large carnivores, perhaps the best known of dinosaurs.
This animation demonstrates the type of engine most commonly used in cars.
This animation introduces the most important organ systems of the human body.
Visit the workshop of the Renaissance polymath and his most influential inventions and works of art.
This animation presents some interesting facts in physical geography.
Reindeer are the northernmost deer species.
The main sources of water pollution are industry, agriculture and urban areas.
The large intestine is the last section of our digestive track.
Typical settlements of the Norsemen were not only established in Scandinavia, they appeared on distant areas as well.
This animation explains transparency and opacity, the principle of radiography, and the light-absorbing properties of materials.