The correct answer is Timbuktu. It became the greatest city because it was a melting pot for traders from all possible nations because it was wealthy and developed compared to other places. It was a cultural and a trading center because the ruler knew how to rule properly and made Timbuktu one of the greatest cities in the world.
Texas was able to become a leader in the aerospace industry because of NASAs headquarters which is located in Houston (aka my hometown :D )
<span>Rome allowed worship of many god, but they also demanded that their Emperor be worshiped as a god and the Christians refused. They would only bow to Jesus.</span>
The first mask was made in 7000 BC. It was used primarily for rituals and ceremonies and where typically made of leather or wood. Keep in mind, these where the first masks that our modern generation has been able to find and preserve, masks could have been made earlier than this but detirriorated over time.
However, the first modern surgical masks where made in the early 1960s and replaced a more primitive method of cloth masks.
I hope I have helped! :)