Arrange the following numbers in descending order:
$-999,$ $899,$ $-566,$ $90,$ $-890,$ $-1.$

Write the absolute value of the following:
$\left|465\right|$

Write the absolute value of the following

$\left|\begin{array}{c}-45\end{array}\right|$

Write the absolute value of the following:
$\left|0\right|$

Write the absolute value of $\left|-901\right|$.