7. In the polar coordinate system, the distance from the point $\left(2,-\frac{\pi}{6}\right)$ to the line $\rho \sin \left(\theta-30^{\circ}\right)=1$ is
7. $\sqrt{3}+1$ Hint: It can be converted to the distance from the point $(\sqrt{3}, -1)$ to the line $\frac{\sqrt{3}}{2} y-\frac{1}{2} x=1$ in the Cartesian coordinate system.