Objects that are too small or too large, events that occur too slowly or too quickly, and processes that are too complicated or too dangerous are most often represented by

Models are used to see objects that too small/large to see, or events that occur too slowly/quickly and processes that are too complicated or dangerous.

Explanation:

Models are used so that they can be studied since the original thing being looked at can't be used for various reasons. Models are easier to use and can be studied at length by scientists, doctors, etc. Many atoms, cells, and isotypes are studied in school using models to learn from. A model can be made of clay, metals, wood, and sometimes food is used in a school setting to study the inside of a cell.