Answer
(a) $-\infty$
(b) $\infty$
(c) $\infty$
(d) $-\infty$
(e) $\infty$
(f) x=-7, x=-3, x=0, x=6
Work Step by Step
To approach questions (a)-(e), you simply look at the graph. When the question gives you a limit, it is asking you to look and see what happens to y as x goes to the number given. If the number has a negative sign on its right, then you look from the left hand side. If it has a positive sign on its right, then you look from the right hand side. If it has no sign, then you look at it from the left and right hand side.
For question (f), you simply look at the x-value that the graph approaches but never touches or crosses and that is your vertical asymptote.