Which one of the following is not bounded on the intervals as indicated

Let a function $f : R \rightarrow  R$ is defined such that $3f(2x^2 -3x + 5) + 2f(3x^2 -2x + 4) = x^2 -7x + 9\ \ \  \forall  x \in R$, then the value of $f(5)$ is-

Range of $f(x) = \;[x]\; – x$ is

Period of $f(x) = nx + n – [nx + n]$, $n \in N$

where [ ] denotes the greatest integer function is :

If $f:R \to R$ and $g:R \to R$ are given by $f(x) = \;|x|$ and $g(x) = \;|x|$ for each $x \in R$, then $\{ x \in R\;:g(f(x)) \le f(g(x))\} = $