In what ways were art and literature key elements in this east asia cultural complex? is it more accurate to think of a common east asian civilization by the postclassical period or to look at the lapanese, korean, and vietnamese societies as separate cases with some interaction with some interactions with china? did the spread of chinese values to other east asian societies suggest any particular relationship between east asia and other parts of the world?

The arts and literature of East Asia have important commonalities. One can justify these connections based on the geographic designations as well as long standing cultural connections between these regions. So the geographic definition would include Southeast Asia in the East Asia cultural complex. Although in much of the literature, the region is treated separately. However, the cultural connections are well established.  These connections are linked to the influence of Buddhism in China. Japan and Korea. China has become the dominant culture to reference in East Asia. Much of this is related to its distinct development. China's two major dynasties, the Han and Tang (618-907) were truly international in scope. Korea's location placed it in a subservient position to China. Japan although more independent than Korea was deeply influenced by Chinese religious practice and philosophy. Moreover, despite the vigorous assertion of national cultures in Japan, Chinese writing styles predominated. Chinese innovations in writing, print and moveable type caused it to play an important and dominant role in literary production.  Japanese literature was heavily influenced by the Chinese as well.  Korean literature was also sometimes produced in classical Chinese.

seeing as no choices were provided, i'll do my best to answer it from knowledge.

job specialization promotes work ethic to the person doing the job. he/she may be strong in the arms and able to lift things, specializing him/her in a job where you lift and carry.

increase in population