2.3 Demonstrate the effectiveness of different models to represent the same thing and the same model to represent different things.
3 The grouping of magnitudes of size, time, frequency, and pressures or other units of measurement into a series of relative order provides a useful way to deal with the immense range and the changes in scale that affect the behavior and design of systems.
3.1 Cite examples of how different aspects of natural and designed systems change at different rates with changes in scale.
3.2 Use powers of ten notation to represent very small and very large numbers.
4 Equilibrium is a state of stability due either to a lack of change (static equilibrium) or a balance between opposing forces (dynamic equilibrium).
4.1 Describe how feedback mechanisms are used in both designed and natural systems to keep changes within desired limits.
4.2 Describe changes within equilibrium cycles in terms of frequency or cycle length and determine the highest and lowest values and when they occur.
5 Identifying patterns of change is necessary for making predictions about future behavior and conditions.
5.1 Use simple linear equations to represent how a parameter changes with time.
5.2 Observe patterns of change in trends or cycles and make predictions on what might happen in the future.