At the heart of the SI is a short list of base units defined in an absolute way without referring to any other units. The base units are consistent with the part of the metric system called the MKS system. In all there are seven SI base units: 1  the meter for distance, 2  the kilogram for mass, 3  the second for time, 4  the ampere for electric current, 5  the kelvin for temperature, 6  the mole for amount of substance, and. 7  the candela for intensity of light.
AA as an academic degree stands for Associates of Arts. The difference between Associates of Arts, Associates of Science, and Associates of Applied Science: Associate degrees fall into three main areas. Associates of Arts (AA)
A.A. Associate of Arts: A two-year degree in any specific liberal art or a general degree covering a mix of courses in liberal arts and sciences. It is acceptable to use the A.A. abbreviation in place of the full degree name.For example: Alfred earned an A.A. at the local community college.aster of Arts: The master's degree is a degree earned in graduate school. The M.A. is a master's degree in one of the liberal arts awarded to students who study one or two years after earning a bachelor's degree.