USE UNITS AS A WAY TO UNDERSTAND PROBLEMS AND TO GUIDE THE SOLUTION OF MULTI-STEP PROBLEMS; CHOOSE AND INTERPRET UNITS CONSISTENTLY IN FORMULAS; CHOOSE AND INTERPRET THE SCALE AND THE ORIGIN IN GRAPHS AND DATA DISPLAYS.
DEFINE APPROPRIATE QUANTITIES FOR THE PURPOSE OF DESCRIPTIVE MODELING.
CHOOSE A LEVEL OF ACCURACY APPROPRIATE TO LIMITATIONS ON MEASUREMENT WHEN REPORTING QUANTITIES.