Click the box next to the Save copy as field so it's selected, and then click the PowerPoint Presentation file from the drop-down list. Select the folder on your computer where you want to save the Keynote file as a PowerPoint file. Click the Save button. Close the Keynote application and open PowerPoint.
This question is archived. That would be igneous rock. Igneous rock is formed by the cooling of molten rock (magma and/or lava). Since there is such and abundance of liquid rock on Earth, it makes igneous rock the most common TYPE of rock.
Silicon is the second most abundant element. Silicon dioxide and silicates (salts derived from silicon dioxide) make up about 87 percent of the materials in the Earth's crust. (Source: Tzimopoulos, Nicholas D., et al. Modern Chemistry, pp. 289, 758.) However water is the most common substance on the surface of the Earth. In the atmosphere, Nitrogen is the most common element (78%). It is believed that the core of our planet is mostly made of iron (at very high pressure and density), so iron would be the most common element within the Earth.