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Consider the statements regarding Earth’s interior and seismic waves.
1) Primary waves totally disappear in the core region revealing that outer core is made up of liquid.
2) Secondary waves show changes in its speed as it travels from magma chamber to lithosphere region indicating difference in density.
3) The speed of secondary waves is highest inside the Earth’s Core region indicating highest density in the Core region.
Choose the correct statement/s from the code below.

1, 2 only.
2 only.
1, 3only.
2, 3 only.
Explanation:
Primary waves (P-waves) are compressional waves that are longitudinal in nature. Thesewaves can travel through any type of material, including fluids, and can travel at nearlytwice the speed of S waves. Thus will not disappear in the core. But S waves do disappear inthe core region.Secondary waves (S-waves) are shear waves that are transverse in nature. S-waves cantravel only through solids, as fluids (liquids and gases) do not support shear stresses. Swavesare slower than P-waves, and speeds are typically around 60% of that of P-waves inany given material. S waves speed varies with density just like P waves and this speedincreases with increasing density. Since there is density difference between lithosphere andmagma chamber the speed of the S waves do change.S waves do not enter the Core region as the outer core is made up of liquid.
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