A compound of material formed by a chemical is known as?

Two friends at different locations want to communicate with each other by sending low energy signals. which of the following methods can they use to communicate? a) produce x-rays using colliding electrons and send them to radios, which capture sound b) send messages using infrared radiation, which travel in the form of waves c) send radio waves through intervening media like radio and television d) produce sound waves using microwaves from heated objects

What two categories of toxins were present in the air at dish,texas as a result of the gas pipelines that pass through the area

Island arcsisland arcs are long, curved chains of oceanic islands associated with seismic activity and mountain-building processes at certain plate boundaries. they occur where oceanic tectonic plates collide. along one side of these island arcs, there is usually a long, narrow deep-sea trench.at island arcs, the denser plate is subducted and is forced into the partially molten mantle under the less dense plate. the islands are composed of the extrusive igneous rocks basalt and andesite. the basalt originates most likely from the plastic mantle. the andesite originates most likely from the melting of parts of the descending plate and sediments that had accumulated on its surface.which list identifies minerals present in andesite from the greatest percentage by volume to the least percentage by volume? a) biotite, plagioclase feldspar, amphiboleb) biotite, amphibole, plagioclase feldsparc) plagioclase feldspar, biotite, amphiboled) plagioclase feldspar, amphibole, biotite