A $8$-node network runs the carrier sense Multiple Access (CSMA) MAC protocol. The maximum data rate of the network is $10$ Megabits/s. Including retries, each node sends traffic according to some unknown random process at an average rate of $1$ Megabit/s per node. Given that the network's utilization is $0.75$. No packets get dropped in the network except due to collisions, and each node's average queue size is $5$ packets. What fraction of packets sent by the nodes (including retries) experience a collision?_________% (correct to two decimal places).
