Our Earth has many resources, but they are not unlimited. In the case of abundant metals, supply will most often meet demand. However, problems can occur when
A) there is a shortage of ores that can be mined at a reasonable cost.
B) high grade ores are depleted and low-grade ores need to be mined.
C) transport and processing costs override economic feasibility.
D) all of the above.
Question 2
The melting point of silicate minerals is strongly dependent on the amount of silica it contains. The first minerals to melt are those with
What will be an ideal response?
