A university's research department is storing large datasets on Amazon S3 for various projects. They have two distinct types of data: "Project Alpha" data is accessed frequently for the first 30 days but will be rarely accessed thereafter. However, when needed, the data must be immediately available. "Project Beta" data is archival and will only be accessed for potential audits, with retrieval time being less critical. What combination of S3 storage classes should the research department use to store "Project Alpha" and "Project Beta" data most cost-effectively?