1. Using the cosmic (primordial solar) abundances of Mg, Si and Fe, estimate the radius of Earth's core. Element Mg Si Fe Atomic 1.03 1.00 0.845 abundance per Si atomAssuming that: 1) 2) 3) 4) 5) The mantle (essentially all of Earth except the core) contains only Mg, 5' and O. Ignore the crust (which is actually not that much different from th mantle anyway, at least for this purpose). The core contains only Fe. The ratio of the number of Mg atoms to Fe atoms or to Si atoms is the same as in the Sun (i.e., same relative cosmic abundance). Assume enough oxygen to charge balance all the Mg as Mg2+ and all the Si as Si'\". [Notez Earth does not have the cosmic abundance of oxygen relative to magnesium or silicon because most of the oxygen was contained in molecules that did not condense when Earth formed]. Earth's core has an average density of 1.05 x 104 kg/m3 (This is larger the iron at Earth's surface because of the extreme pressures). Earth's mass is 5.97 x 1024 kg. Atomic masses are adequately approximated as O=16.0, Mg=24.3, Si=28.1, Fe=55.8. Avogadro's number is 6.02 x 1023, though you don't actually need it; it will cancel out even if you do introduce it. All the information you need has been provided