When you think of a channel think of trade. Or boats going up and down a stream, a channel is a body of water.
The purposes of government include maintenance of a social order, providing public services, providing national protection and making national economic decisions.
Answer:
Nung Shu is considered the world's first mass-produced book. It was exported to Europe and, coincidentally, documented many Chinese inventions that have been traditionally attributed to Europeans.
Your answer is cognitive-behavior therapy. (:
