Answer
$K_2SO_4$ is a strong electrolyte.
Work Step by Step
As the equation shows, $K_2SO_4$ when dissolved in water, is divided into $K^+$ and $SO_4$ ions.
Since the arrow only points to the right side, we can assume that $K_2SO_4$ is completely transformed into $K^+$ and $SO_4^{2-}$, and this is the main characteristic of a strong electrolyte.
