When a mineral reserve is considered to be depleted, what is the typical percentage of mineral left in the ground?
A. 20%
B. 0%
C. 5%
D. 50%
Answer: A
You might also like to view...
The Canadian region receiving the most federal economic aid is
A. the Atlantic provinces B. Quebec C. The Prairie provinces D. British Columbia
Agriculture originated when ________
A) humans domesticated plants and animals for their use B) people decided that hunting was too difficult C) people came together to divide the earth into farming plots D) kings forced their subjects to stay in towns and villages E) when wives forced their husbands to get into the field and get food
How do organic compounds differ from inorganic compounds?
A) Inorganic compounds never contain carbon, whereas organic compounds always contain carbon. B) Inorganic compounds always only consist of two atoms. C) Organic compounds are always acidic, while inorganic compounds are always basic. D) Organic compounds consist of carbon atoms joined by covalent bonds and may contain other elements, such as nitrogen, oxygen, sulfur, and phosphorus. Inorganic compounds lack carbon-carbon bonds. E) A and C are correct.
________ is the process by which thickened crust adjusts over time to a "normal" thickness
A) Subduction B) Convection C) Accretion D) Isostacy