diseases from Europeans killed many native Americans because they were not immune to those diseases
The most likely reason Persia gave economic control to Russia and Britain was because they were torn from a revolution and needed the injection of cash and credit that this transfer would bring.
According to Herodotus, the Phoenician prince Cadmus was accredited with the introduction of the Phoenician alphabet—phoinikeia grammata, "Phoenician letters"—to the Greeks, who adapted it to form their Greek alphabet.
B. Because even with many issues that plagued the Roman Empire economically and politically, By the later years of the empire the Roman military was mainly comprised of trained Barbarian soliders who were inferior to earlier Roman soliders causing a significant decrease in the Roman Empires's Military capablities so many barbarian tribes that began to grow such as the Huns, Vandals, Goth etc. Put immense pressure on the Empire, driving them into the ground economically and causing many issues within the government and eventually being sacked, thus marking the end of the Roman Empire. Sorry for the wall of text but hope this helped :)
Answer
Virtual realism lost much of its appeal due to the difficulty in creating lifelike images.
Explanation
Virtual reality is a high-end user interface which involves real-time simulation and interaction through multiple sensational channels. Sound, vision, taste ,smell and touch are the five senses that are used in virtual reality.
It has set of independent rotations that completely specifies the position and the orientation of the system. Or an environment that can be interacted with seemingly real or physical way by somebody using special electronic equipment's such as 3D screens.