Question

Please help me complete the missing word. Thanks!!?

Answer 1

One of the "firsts" of this era was the development of iron casting.

Explanation:

That dynasty saw many significant developments in science, technology and religion. More of them can be learned here:

http://www.apworldhistory101.com/history-of-china/zhou/

https://ancientchinesedynasties.weebly.com/the-zhou-dynasty.html

https://www.reference.com/history/inventions-china-during-zhou-dynasty-e90a6ad1bf7d0b46