Answer
$-8$
Work Step by Step
We know if $f$ is a polynomial function and $a$ is any real number, then $\lim\limits_{x \to a}f(x)=f(a)$.
Hence since $8(t-5)(t-7)$ is a polynomial (in factored form), we have $\lim\limits_{t \to 6}8(t-5)(t-7)=8(6-5)(6-7)=8(1)(-1)=-8.$
