How can i find the length of a chord?

Oh, that's simple. Look at the sentence before her statement of Hitler being violent. She stated how he "ordered the murder of millions of ethnic minorities-...", which expresses a violent act carried out by his instruction.

Explanation:

"Adolf Hitler is maybe the most infamous person in history. As the leader of Germany before and during World War II, he promoted racist ideas and ordered the murder of millions of ethnic minorities, especially Jews. He rose to power during a time of crisis in Germany, and his cruel, violent legacy is often seen as a warning to the rest of the world of what can happen when someone is too obsessed with national pride and racial superiority."

Hope this helps! :)