Question 92
In a plane rectangular coordinate system $xOy$, $\Gamma_1$ is a unit circle centred at $(2, 1)$ and $\Gamma_2$ is a unit circle centred at $(10, 11)$. Make a line $l$ through the origin $O$ such that $l$ has two intersections with each of $\Gamma_1$ and $\Gamma_2$, dividing $\Gamma_1$ and $\Gamma_2$ into four arcs, and two of these four arcs are of equal length. The sum of the slopes of all the lines $l$ satisfying the conditions is ________.