A regular square pyramid is a right pyramid with a square base and four triangular faces.
Regular dice can be used for solving statistical and probability exercises.
Groundwater and aquifers are types of underground waters.
These special dolmens located in present-day Netherlands were built about 5,000 years ago.
The Hussites mastered the use of war wagons in the 15th century.
The Pula Arena, located in present-day Croatia, was one of the largest Roman amphitheatres in the Antiquity.
Waterfalls form where a river flows over a steep precipice in its course.
A hot air balloon is a balloon aircraft which is lifted by hot air.
This stunning castle is situated in northern Croatia.
Water turbines convert the kinetic energy of water into electric current.
Domesticated animals and crops originate from various parts of the world.
Structures consisting of enormous stone blocks, dating back thousands of years, are monuments of megalithic cultures.
This animation demonstrates the main sources of soil pollution.
In summer, monsoon winds bring heavy rainfall from the ocean to the continent.
To calculate the volume of a tetrahedron we start by calculating the volume of a prism.
Polypeptide chains are composed of amino acids and can appear in alpha-helix or beta-sheet form.
Division of space by three intersecting planes in several different arrangements.
The United States entered World War II after the devastating attack by the Japanese navy.
The oxygen cycle describes the movement of oxygen within its three main reservoirs.
The phosphorus cycle describes the movement of phosphorus through the lithosphere, hydrosphere, and biosphere.