Hint: Let $\gamma_R$ be a circle of radius $R$ around 0 such that all zeros of $q$ lie inside $\gamma_R$. What can you say for $\int_{\gamma_R} \frac pq \, dz$ for $R \to \infty$? How can you connect this with the residue sum?

sum of the residue at all poles of the rational function p/q is 0.
Some web hosting providers offer "kvm reboot" for their dedicated servers? What does that mean?

Does it mean the server reboots automatically after a crash or freeze?
