Mandy's "save the whales" speech was very effective because she started off with stories about her personal experience with whales, then she moved into facts, statistics, and sources. which principle of supporting material organization did mandy effectively use in her speech?

The best answer to the question: Which principle of supporting material organization did Mandy effectively use in her speech? Would be: Going from soft to hard evidence, or from personal experience, to concrete data and evidence

Explanation:

Mandy gave a speech in which she most likely wanted to persuade her audience about the importance and the magnificence of whales, as well as how important protecting them was. Because she wanted to first produce a connection between her audience and herself through familiarity and emotional connection, she uses her personal experiences with whales (soft evidence) and with it brings in an interest in her listeners that goes beyond what is purely factual and scientific. Then, when that personal connection has been accomplished, she starts to reveal the hard evidence she has on whales through the release of statistics, sources and facts, to further support the arguments she most likely made through her soft evidence. This is the characteristic of the principle of supporting material organization mentioned in the answer.