By the 1960’s the scientific community had largely accepted the idea of plate tectonics. Leading to this general acceptance of the theory were a large number of findings from the post World War II era. One of the most compelling pieces of evidence supporting the plate tectonic theory was the discovery of magnetic striping: zebra-like stripes indicating regions of strongly magnetic rock separated by magnetic rocks with opposite polarity on the seafloor surrounding the Mid-Atlantic Ridge. These magnetic stripes on the ocean floor were used to show that— A: the seafloor was spreading outward from the Mid-Atlantic Ridge and that sections of the seabed had been formed during different time periods.

B: the seafloor was spreading inward toward the Mid-Atlantic Ridge and that sections of the seabed had been formed during different time periods.

C: the seafloor was effectively stationary, but continental landmasses had significantly shifted coastlines over time.
D: natural magnetic rocks always form deep in the mantle of the Earth, demonstrating that the crust had changed over time.

Consider three unlabeled bottles, each contain small pieces of one of the following metals. - magnesium - sodium - silver the following reagents are used for identifying the metals. - pure water - a solution of 1.0 molar hcl - a solution of concentrated hno3 (a) which metal can be easily identified because it is much softer than the other two? describe a chemical test that distinguishes this metal from the other two, using only one of the reagents above. write a balanced chemical equation for the reaction that occurs. (b) one of the other two metals reacts readily with the hcl solution. identify the metal and write the balanced chemical equation for the reaction that occurs when this metal is added to the hcl solution. use the table of standard reduction potentials (attached) to account for the fact that this metal reacts with hcl while the other does not. (c) the one remaining metal reacts with the concentrated hno3 solution. write a balanced chemical equation for the reaction that occurs. (d) the solution obtained in (c) is diluted and a few drops of 1 m hcl is added. describe what would be observed. write a balanced chemical equation for the reaction that occurs.

Which statements are true concerning mineral formation? check all that apply. the slower the cooling, the larger the crystals. the faster the cooling, the smaller the crystals. crystals formed from magma are smaller than crystals formed from lava. minerals can only form in solutions when the solution is heated deep underground. when a solution cools, elements and compounds leave the solution and crystallize as minerals. minerals formed from hot water solutions can form narrow channels in the surrounding rock.

Arectangle has a diagonal 20 inches long that forms angles of 60 and 30 with the sides. find the perimeter of the rectangle. for geometry