The rolling magma causes uneven currents in underneath the earths crust. Sort of similar to wind patterns in the sky but think of them as underground and in a much thicker fluid. Ocean currents might be a better analogy. Because of it being a much more viscous fluid, there is greater pressure buildup which can cause torsion, compression, expansion etc. when you bake a cake look how the dough underneath expands & the top crust cracks and stretches. Hope that helps.
Explanation:
The group number in the periodic table represents number of valence electrons of the elements in a certain group.
Group 1 : 2,8,1
Group 2 : 2,8,8,2
Group 3 : 2,8,3
Group 4: 2,4
Group 7 : 2,8,7
106.4 is going to be your answer
3 cubic centimeters, Volume= density/ mass
Thallium has got 81 protons
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