"How did medieval Europe change after the Crusades? Give me TWO examples" pls help

Millions of lives were lost due to the Crusades; However, many new advancements were spread because of the Crusades.

The Europeans learned about new concepts in math as well as a new numbering system, called Hindu Arabic Numerals, which we still use today. They gained access to new medical knowledge and a variety of other ideas. The Crusades also opened up many new trade possibilities with goods that Europeans never had access to before them.

I’m pretty sure it’s 4, you can check on the calculator