According to Ptolemy's model, he, too, believed in a geocentric Universe and that the planets and stars were perfect spheres, though Earth itself was not.
He further thought that the movements of the planets and stars must be circular since they were perfect and, if the motions were circular, then they could go on forever.
<h3>What is comets and shooting stars?</h3>
Shooting stars are very different from comets, although the two can be related. A Comet is a ball of ice and dirt, orbiting the Sun (usually millions of miles from Earth). ... A shooting star on the other hand, is a grain of dust or rock (see where this is going) that burns up as it enters the Earth's atmosphere.
Learn more about ptolemy's model:
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The diaphragm is primarily an involuntary muscle. Although voluntary means can be achieved, such as when you hold your breath while swimming, this is temporary as the diaphragm will eventually work on its own to supply your body with oxygen.
In normal fission reactors, the fuel used to start the nuclear fission is Uranium-235.
Generally, fuel rods enriched with uranium-235 are used to start the fission. When a nucleus of uranium-235 absorbs a neutron, it becomes unstable and then it breaks apart, producing two smaller nuclei, several neutrons and energy. The additional neutrons produced in the reaction are then absorbed by other nuclei of uranium-235, triggering other fission reactions, and so on.
Esta energía<span> puede ser convertida en otras, como calor para calentar agua o edificios, invernaderos etc. o electricidad. Podemos convertir la </span>energía<span> solar en eléctrica de dos </span>formas<span>: Fotovoltáica (PV): La radiación solar se convierte directamente en electricidad
hope this help mark brainliest plz</span>
Answer:
12 (Magnesium- Mg)
Explanation:
Looking at the four numbers, we have:
Magnesium, Silicon, Sulfur, and Chlorine.
We can eliminate two of the answers immediately just by looking at the periodic table.
Sulfur and Chlorine are on the nonmetal side of the periodic table. So that's <em>definitely</em> not it. That leaves Magnesium and Silicon.
Silicon is a Metalloid. Magnesium is an Alkaline earth Metal.
Metaloids are elements that have a mix of both<em> metal</em> and<em> nonmetal </em>properties (luster, how it feels, etc.). Since it's a MIX and Magnesium is just straight METAL-
We can say Magnesium has the most metallic properties.
hope this helps!!
