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Which of the following statements are correct?
(i) The second period \( (n=2) \) starts with lithium and third electron enters the \( 2 s \) orbital. The next element, beryllium has four electrons and has the electronic configuration \( 1 s^{2} 2 s^{2} \). From the next element boron, the \( 2 p \) orbitals are filled with electrons when the \( \mathrm{L} \) shell is completed at neon \( \left(2 s^{2} 2 p^{6}\right) \). Thus there are 8 elements in the second period.
(ii) Successive filling of \( 3 s \) and \( 3 p \) orbitals gives rise to the third period of 8 elements from sodium to argon.
(iii) The fourth period \( (n=4) \) starts at potassium and the added electron fill up the first \( 4 s \) and \( 4 p \) orbitals than \( 3 d \) orbital is filled.
(iv) Fifth period begins with rubidium with the filling of \( 5 \mathrm{~s} \) orbital and ends at xenon with the filling up of the \( 5 p \) orbital.
(a) (i) and (ii)
(b) (i), (ii) and (iii)
(c) (iii) and (iv)
(d) (i), (ii) and (iv)
\( \mathrm{P} \)
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