Yes that answer above is correct
there are more than 200 countries in the world
Well if you mean what does the controlled part of a scientific investigation, it is the part of the investigation that will be your control or your base, untouched, original, data and such.
Answer:
Silicate-Oxygen tetrahedro
Explanation:
Silicate-Oxygen tetrahedro are the most abundant and basic structure of common minerals.
These are silicate minerals which formed to silicate rock forming mineral. These constitute about 90% of earth crust. Silica SiO2 consider as most common mineral on the surface of earth also known as Quartz. The the most andundant element in the earth crust is oxygen, mainly found in combine form.
