Final answer:
SI units are an improved version of MKS units because of their convenience and simplicity in scientific and engineering calculations. They are categorized by factors of 10, which makes conversions between units easier.
Step-by-step explanation:
SI (International System of Units) units are an improved version of MKS (meter, kilogram, second) units due to their convenience and simplicity in scientific and engineering calculations. The metric system, including SI units, is categorized by factors of 10, making conversions between units easier. All metric units are based on multiples of 10, allowing for simple scaling using metric prefixes.