20. Placer deposits form when ____. (1 point)

hot, metal-rich fluids cool underground
heavy eroded particles settle out of moving water
organic matter is compressed over millions of years
magma cools in underground chambers

21. Which of the following is a nonmetallic mineral resource? (1 point)

wood
coal
iron
aggregate

Question

20.   Placer deposits form when ____.  (1 point)

hot, metal-rich fluids cool underground
    heavy eroded particles settle out of moving water
    organic matter is compressed over millions of years
    magma cools in underground chambers

21.   Which of the following is a nonmetallic mineral resource?  (1 point)

wood
    coal
    iron
    aggregate

anonymous · Answer

wood coal and aggregate are nonmetallic mineral resource

anonymous · Answer

placer deposits are formed below the surface  and  rise to the surface where they are eroded by a river seperating the mineral from the bedrock (gold or diamonds)

anonymous · Answer

I need the answer to both too?