/kloc-was there a plastic pinion 0/00 years ago?

Not yet. The invention time of plastics was 1909, but at that time, plastics could not be used to make other articles. It was not until 1960 that plastics were used to make articles, and the application of gears was also in this period, so by 2022, the invention of plastic gears would be 62 years apart.

The major of economic statistics introduces what is economic statistics.

Futures bosses go out

Dear futures experts, I have been puzzled for a long time. Why does futures exist? It is said on the Internet that futures trading generally only closes positions, and there will be no physical transa

What is the daily limit of Zanyou option?

The price of pigs rose to a new high, the price of eggs collectively "dived" and the price of sheep hit a new low. What happened?

What does it mean to see a big order at the limit?

How to open the flush sub-picture?

What about Xi' an twilight information technology co., ltd?

What are the delisted stocks?

Reasons for the collapse of Andersen