What is the efficiency of an Ethernet protocol CSMACD with c

What is the efficiency of an Ethernet protocol (CSMA/CD) with contention and a large number of nodes what with 1000Mbps speed and maximum distance between any two nodes 1 km?

Solution

maximum efficiency of CSMA/CD with usual formula:

Frame time/(Frame time+ Overhead)

= Frame time/(Frame time+ average contention interval)