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Not all nets consisting of 6 congruent squares are foldable into cubes.
The devastating defeat of the Hungarians in the battle against the Mongolians was the result of several bad decisions.
An exercise about the groups and structure of organic nitrogen compounds.
Lateral compressive forces cause rocks to form folds. This is how fold mountains are formed.
An exercise about the groups and structure of oxo compounds.
Edges, diagonals and faces of a cuboid can be identified by its vertices.
Several political and economic unions have been formed between countries during the past decades.
Pick the shape that is shown in different views below.
The sum of the volume of the ´tetrahedrons´ gives an approximation of the volume of the sphere.
Water on Earth is in a continuous state of change. The water cycle includes processes such as evaporation, precipitation, melting and freezing.
An exercise about hydrocarbons.
A heterocyclic organic compound, its derivatives are thymine, cytosine and uracil.
A dynamo converts mechanical energy into direct current.
Clothing reflects the lifestyle and culture of the region's inhabitants.
A colorless, odorless gas, an important component of the atmosphere, indispensable to sustain terrestrial life.
Colorless, odorless, heavier-than-air gas. Necessary for the photosynthesis of plants.
Colorless, odorless gas, highly toxic to humans and animals in high concentration.
A colorless, odorless, non-reactive gas, it constitutes 78.1% of Earth´s atmosphere.
The Forbidden City is one of the most magnificent and mysterious monuments of imperial China.
What happens in a liquid during evaporation and boiling? What does its boiling point depend on?