An RAE cannot be directly converted into an IU without knowing the source(s) of vitamin A. For example, the RDA of 900 mcg RAE for adolescent and adult men is equivalent to 3,000 IU if the food or supplement source is preformed vitamin A (retinol).
On the other hand, an Associate degree is a title conferred on a student when he completes a college study. Diploma is usually given in vocational or professional courses, like designing, pharmacy and engineering. High schools, trade colleges and professional schools confer Diploma certificates.
But in fact, a certificate is different from a diploma. A diploma is a document issued at the completion of a course by an educational institution, which states that the recipient successfully completed the study. Diplomas also can confer an academic degree to the recipient.