$\begin{array}{1 1}(1)\;\text{The complex is octahedral}\\(2)\;\text{The complex is an outer orbital complex}\\(3)\;\text{The complex is }d^2sp^3\;\text{ hybridized}\\(4)\;\text{The complex is diamagnetic}\\(5)\;\text{The coordination number is 6}\end{array}$
$\begin{array}{1 1}(a)\;1,4\\(b)\;1,2,5\\(c)\;2,3,5\\(d)\;2,3\end{array}$