This question is under the topic of Software Engineering in general

In regards to the Agile method "Scrum" and the Waterfall method as Software life cycle methodologies,

Explain the following and give:

1. A Paragraph or two with bullets on best solution to use each methodology. 2. A Paragraph or two with bullets on challenges between gates or check points for each methodology 3. Identify and explain what is the biggest risk in using each methodology?