#### Answer

$\color{blue}{-12, -6, -\sqrt{4}, 0, \text{ and } 6}$

#### Work Step by Step

The set of integers is: $\left\{...-3, -2, -1, 0, 1, 2, 3, ...\right\}$
The set of rational numbers contain all the numbers that can be expressed as $\dfrac{p}{q}$ where $p$ and $q$ are integers and $q \ne 0$.
Note that:
$-\sqrt{4} = -2$
Thus, the integers among the elements of $K$ are:
$\color{blue}{-12, -6, -\sqrt{4}, 0, \text{ and } 6}$