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6.During weathering, iron in minerals typically:A) Dissolves and washes away to the ocean, to be used in shells.B) Dissolves and washes away to the ocean, to react with sea-floor rocks at spreading ridges.C) Rusts, becoming part of the soil, later to be transported as solid particles tocontribute to sediment in the ocean.D) Is unchanged; the iron-rich minerals break out of the rocks and then form sand particles in the soil.E) Washes away as chunks, which react with hot sea-floor rocks at spreading ridges to change the composition of the mantle.Feedback: Iron does rust. If no oxygen were present, then the iron would dissolveand wash away; and indeed, the presence of very old iron ores that formed in oceans suggests that the early Earth lacked free oxygen in the atmosphere but had oxygen-producing bacteria in the ocean, so the iron washed into the ocean, met the iron there, rusted and fell to the bottom. But with our modern, oxygenated atmosphere, iron rusts, contributes to soil, and later is transported to oceans to make sediment there.Correct Answer(s):CPoints Earned:1.0/1.07.Weathering attacks a granite in Pennsylvania or Washington, DC, or a similarly rainy place. The feldspar grains in the granite primarily:
Points Earned:1.0/1.08.It is almost always interesting to ask whether most of the “action” comes from thefew, rare events, or the many common events. For earthquakes, we saw that mostof the energy is released by the few, big events. For mass movement, averaged over the land surface and over thousands of years, which moves the most material: