The Brainliest Answer!
According to neil bohr's theory,
the outermost shell should only contain 8 electrones.if it is more than 8,then it will move to the next it cant be 9

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1)the capacity of the 3rd shell is only 8 can hold only 8 electrons.
2)also according to neir bohr's octet rule the last shell can hold only 8 electrons
no shell has the capacity to hold 9 electrons.thus 2,8,8,2 is only the correct one.

hope tis helps u...
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