Answer
$f(30)=70$.
The government tax revenue is $\$70$ at the tax rate of $30\%$.
The point is $(30,70)$.
Work Step by Step
The given function is $f(x)=\frac{80x-8000}{x-110}$, $30\leq x\leq100$.
Replace $x$ with $30$.
$\Rightarrow f(30)=\frac{80(30)-8000}{30-110}$
Simplify.
$\Rightarrow f(30)=\frac{2400-8000}{-80}$
$\Rightarrow f(30)=\frac{-5600}{-80}$
$\Rightarrow f(30)=70$.
Hence, the government tax revenue is $\$70$ at the tax rate of $30\%$.
The point on the graph of the function is $(30,70)$.
