Can I interconnect two Fast-Ethernet hubs 20m (65ft) apart? And 200m (650ft)?

Interconnecting two class II repeaters by UTP is limited to 5m (16ft) only! Thus you must use fiber connection to exceed this distance,unfortunately- not by much - the new limit is 16m (53ft). You still don't get your 20m, not to mention 200m. A simple solution will be to convert to fiber by using FT-801/FT-802 converters at both hubs - and you can extend the distance between them to 2000m (6500ft)!