Practice the Russian alphabet, build words from letters.
Practice the English alphabet, build words from letters.
Practice the German alphabet and form words from the letters.
A presentation of the major administrative units of China.
Cossacks, members of independent semi-military communities, played an important role in the history of Ukraine.
Remarkable civil engineering works to continue the Netherland's centuries-long fight against the sea.
This 3D scene explains the correlation between the ratio of similarity and the ratio of volume of geometric solids.
The mosque, built in a distinctive architectural style, is the largest adobe structure in the world.
Colorless, odorless liquid produced by dissolving carbon dioxide in water.
The American bison is the largest land animal in North America.
There are various types of instruments used for measuring temperature.
Rimac Automobili's first model is known as the world's fastest production electric vehicle.
A polynucleotid made up of phosphoric acid, ribose, and nucleobases (cytosine, uracil, adenine and guanine).
The apple is one of the most popular fruits around the world.
This animation presents the states and state capitals of Austria.
Formic acid is the simplest carboxylic acid.
Entertaining and spectacular animation to practice orientation in space.
The arms are moved by flexor and extensor muscles.
The two main parts of the central nervous system, the brain and the spinal cord are protected by the skull and the spinal column.
Bones of the lower limbs are connected to the trunk by the pelvis.