Why is cyanide heap leaching used to extract gold from some deposits?

Mexico city is an example of how humans alter their environment because it was a. one of the world’s largest cities b. built on drained and filled lake beds c. built after conquest by the spanish d. once the capital of the aztec empire

What statement about the economy of france is not true? a. paris is a major manufacturing center b. marseille is a busy seaport on the mediterranean coast c. farming is the major activity in the alps. d. world-famous wines are produced in the bordeaux region c. farming is the major activity in the alps

In russia which of these challenges affects the transportation of both petroleum products and other goods?