Let

$f(x)=\frac{-2}{(2-x)(2+x)},f^{\text{'}}(x)=\frac{-4x}{(2-x{)}^2(2+x{)}^2},$ and $,f^{\text{'}\text{'}}(x)=\frac{-4(4+3x^2)}{(2-x{)}^3(2+x{)}^3}$

$[18]($a$)$ Provide the following requested information about the function $f(x)$ and its graph. GIVE ANSWERS ONLY; do rough work on the attached blank pages. Answer "NONE" for any item that does not exist.

$\backslash$table$[[$Domain$,],[$Equation$($s$)$ of horizontal asymptote$($s$),],[$Equation$($s$)$ of vertical asymptote$($s$),],[$Critical number$($s$),],[$Open interval$($s$)$ where $f$ is increasing,$],[$Open interval$($s$)$ where $f$ is decreasing,$],[x$ and $y$ coordinates of all relative maxima,$],[x$ and $y$ coordinates of all relative minima,$],[$Open interval$($s$)$ where $f$ is concave upward,$],[$Open interval$($s$)$ where $f$ is concave downward,$],[x$ and $y$ coordinates of all inflection point$($s$),]]$