Please answer the following questions about the function

$f(x)=\frac{2x-4}{x+5}$

Instructions: If you are asked to find a function, enter a function. If you are asked to find $x-$ or $y-$values, enter either a number, a list of numbers separated by commas, or None if there aren't any solutions. Use interval notation if you are asked to find an interval or union of intervals, and enter $\{\}$ if the interval is empty.

$($a$)$ Calculate the first derivative of $f.$ Find the critical numbers of $f,$ where it is increasing and decreasing, and its local extrema.

$f^{\text{'}}(x)=$

Critical numbers $x=$

Increasing on the interva

Decreasing on the inten

Local maxima $x=$

Local minima $x=$

$($b$)$ Calculate the second derivative of $f.$ Find where $f$ is concave up$,$ concave down, and has inflection points.

$f^{\text{'}\text{'}}(x)=$

Concave up on the interval

Concave down on the interva

Inflection points $x=$

$($c$)$ Find any horizontal and vertical asymptotes of $f.$

Horizontal asymptotes $y=$

Vertical asymptotes $x=$