Electronic configuration of deuterium atom is

$(I)\,\,B{r^ - }{\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} $ $(II)\,\,\begin{array}{*{20}{c}}
{{\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} O{\mkern 1mu} } \\
{{\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} ||} \\
{{H_3}C - C - {O^ - }}
\end{array}$ $(III)\,\,C{H_3}C{H_2}{O^ - }$ $(IV)\,\,Ph - {O^ - }$

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Which of the following statement is correct

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The increasing order of basicity for the following intermediates is (from weak to strong)

$(i)$ $\begin{array}{*{20}{c}}
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,C{H_3}} \\
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,|} \\
{C{H_3} - {C^ \mathbf{-} }} \\
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,|} \\
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,C{H_3}}
\end{array}$

$(ii)$ $H _{2} C = CH - CH _{2}$

$(iii)$ $HC \equiv \stackrel{\ominus}{ C }$

$(iv)$ $\stackrel{\ominus}{ CH _{3}}$

$(v)$ $\stackrel{\ominus}{{ }_{ CN }}$

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Which of the following molecules has trigonal planer geometry

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An element, $X$ has the following isotopic composition :

$^{200}X \,:\, 90\%$ $^{199}X\, :\, 8.0\%$ $^{202}X\, :\, 2.0\%$

The weighted average atomic mass of the naturally occurring element $X$ is closest to......$amu$

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On catalytic reduction $(H_2 /Pt)$ how many alkenes will give $n$ -butane ?