Through peaceful talks and non-violent demonstrations.
Answer: It includes firsthand accounts of the fire and its aftermath
Explanation:
Jim Murphy’s "The Great Fire" is considered a credible source because it includes firsthand accounts of the fire and its aftermath.
A material is considered a credible source of it's provided by an eye witness or has first hand Information on a particular topic.
It is true that scientists are able to calculate between objects in space by seeing how much time it takes light to travel between objects