Thank you for the opportunity to help you with your question!
"Scientific manner" means "Scientific method", which is what the question is asking. The steps of the scientific method are generally agreed to be:
Ask a Question
Do research to determine what is known and not known
Construct a hypothesis
Test hypothesis with experimentation
Analyze experimental data
A bit more is included, but for our purposes, we'll stop there.
"Evidence" in this case means "I have a definitive question I would like to answer. In order to do so, I have conducted these experiments to collect data that will yield the information I need to draw conclusions about how to answer the question."
In short, evidence is the result of experimentation that allows you to either accept your original question or to reject it. "Evidence" is the experimental result that supports your hypothesis... Or refutes your hypothesis.
Please let me know if you need any clarification. I'm always happy to answer your questions.
Oct 21st, 2015
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