Answer:
Basaltic magma -- SiO2 45-55 wt%, high in Fe, Mg, Ca, low in K, Na
Andesitic magma -- SiO2 55-65 wt%, intermediate. in Fe, Mg, Ca, Na, K
Rhyolitic magma -- SiO2 65-75%, low in Fe, Mg, Ca, high in K, Na
Explanation:
Protection of water sources
soils formation and protection
nutrient storage and recycling
pollution breakdown and absorption
contribution to climate stability
maintenance of ecosystems
recovery from unpredictable events
Answer:
Rank of the stars from shortest to longest distances:
Barnard's Star (M4)
61 Cygnia A (K5)
Alpha Centauri A (G2)
Sirius (A1)
Spica (B1)
Explanation:
The habitable zone, also known as the circumstellar habitable zone, is the range of distances from a star where it is not too hot and not too cold for liquid water to exist on the surface of surrounding planets.
The location of a star’s habitable zone is dependent upon its luminosity, which is the amount of light emitted by an object in a unit of time, because a star’s luminosity increases with time; and also the star's mass.
The inverse square law of light brightness can be used to determine the extent of the habitable zones for different luminosity stars with the formula:
star boundary = Sun boundary × squareroot[(star luminosity)/(Sun luminosity].
Explanation:
urban areas are mostly characterised by high population advanced technology and basic amenities. The population helps to increase productivity which leads to economic development, employment opportunities that promotes increase in standard of living which in turn helps economic development.