$K=\mu_0+z_{0.05}\,\sigma/\sqrt n$ with $\sigma=2$

In a normal population $N(\mu,\sigma^2)$ with $\sigma^2=4$, in order to test the null hypothesis $\mu=\mu_0$ against $H_1:\mu=\mu_1$, where $\mu_1>\mu_0$ based on a random sample of size $n$, the value of K such that $\bar X>K$ provides a critical region of size $\alpha=0.05$ is: