Question 119·Medium·Nonlinear Equations in One Variable; Systems in Two Variables

$K = \dfrac{1}{2}mv^2$

The kinetic energy $K$, in joules, of an object is modeled by the formula above, where $m$ is the mass of the object, in kilograms, and $v$ is its speed, in meters per second. Which of the following expresses $v$ in terms of $K$ and $m$?