Minerals that are valued because they contain large amounts of a useful element are called a. ore b. industrial mineral c. gem-bearing mineral d. silicate

The right option is; A. ore

Minerals that are valued because they contain large amounts of a useful element are called ores.

Ores are naturally occurring rock substances that contains large amount of utilitarian materials, usually metals or gems that can be extracted profitably from the deposit. The extraction of the ores from the earth is done through mining and they are processed to remove the valuable elements. Ores are grouped based on their formation and they include; magmatic or volcanic ores (such as iron and copper ores), carbonate alkaline ores (such as diamonds) and metamorphic ores (such as silver, lead and zinc ores).

correct answer is option a.

tropopause, stratopause and mesopause have all in common aspect that is point of maximum temperature in its layer of the atmosphere. all layers of atmosphere observe abrupt change in temperature. tropopause is the boundary between troposphere and stratosphere. stratopause is the boundary between stratosphere and mesosphere. mesopause is the boundary between mesosphere and thermosphere. these all boundaries are ranges between altitude of 0 to 80 km.