Why does electronegativity decrease from right to left within a period?

In which layer of earth do most earthauakes occur a_ inner core b_outer core c_mantle d_crust

Which of the following statements about hybrid orbitals is or are true? choose all that apply. choose all that apply. under sp2 hybridization, the large lobes point to the vertices of an equilateral triangle. after an atom undergoes sp hybridization there is one unhybridized p orbital on the atom. the angle between the large lobes of sp3 hybrids is 109.5∘

Write the overall equation for the reaction occurring in lithium battery?