In 2006–07, researchers from the Wildlife Conservation Society studied gorillas in heavily forested regions centered on the Ouesso district of the Sangha Region. They suggest a population on the order of 125,000 Western Lowland Gorillas, whose isolation from humans has been largely preserved by inhospitable swamps.
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): What was responsible for maintaining the separation between the gorillas and humans?
Ah, so.. inhospitable swamps

As the Roman Empire was falling apart, Palermo fell under the control of several Germanic tribes. The first were the Vandals in 440 AD under the rule of their king Geiseric. The Vandals had occupied all the Roman provinces in North Africa by 455 establishing themselves as a significant force. They acquired Corsica, Sardinia and Sicily shortly afterwards. However, they soon lost these newly acquired possessions to the Ostrogoths. The Ostrogothic conquest under Theodoric the Great began in 488; Theodoric supported Roman culture and government unlike the Germanic Goths. The Gothic War took place between the Ostrogoths and the Eastern Roman Empire, also known as the Byzantine Empire. Sicily was the first part of Italy to be taken under control of General Belisarius who was commissioned by Eastern Emperor. Justinian I solidified his rule in the following years.
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): Who's decline left Palermo under the control of the Roman Empire?
Ah, so.. unanswerable

The Appalachians are also home to two species of fir, the boreal balsam fir (Abies balsamea), and the southern high elevation endemic, Fraser fir (Abies fraseri). Fraser fir is confined to the highest parts of the southern Appalachian Mountains, where along with red spruce it forms a fragile ecosystem known as the Southern Appalachian spruce-fir forest. Fraser fir rarely occurs below 5,500 ft (1,700 m), and becomes the dominant tree type at 6,200 ft (1,900 m). By contrast, balsam fir is found from near sea level to the tree line in the northern Appalachians, but ranges only as far south as Virginia and West Virginia in the central Appalachians, where it is usually confined above 3,900 ft (1,200 m) asl, except in cold valleys. Curiously, it is associated with oaks in Virginia. The balsam fir of Virginia and West Virginia is thought by some to be a natural hybrid between the more northern variety and Fraser fir. While red spruce is common in both upland and bog habitats, balsam fir, as well as black spruce and tamarack, are more characteristic of the latter. However balsam fir also does well in soils with a pH as high as 6.
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): In what state are Fraser firs associated with oaks?
Ah, so..
unanswerable