For the function $f$ whose graph is given, state the value of the given quantity below.

(a) $\displaystyle \lim_{x \to 1^-} f(x)$ help (limits)
(b) $\displaystyle \lim_{x \to 1^+} f(x)$
(c) $\displaystyle \lim_{x \to 1} f(x)$
(d) $\displaystyle \lim_{x \to 5} f(x)$
(e) $f(5)$