Answer:
Mainly technological advancements.
Explanation:
Memoir is a personal legacy written so we can call it a historical source but not document. It is not an evidence, a report or not even a record. It is more like an autobiography or a biography from memorial times. It is a legacy written by a person for a person.
What? Do you need help on I’m confused
Charlie’s friends are good to him because they all forgave him after he made a huge mistake. It did take them awhile to forgive him but it did happen eventually.