Choose all the answers that apply. models are used to observe phenomena which happen too slowly} happen too quickly} are too large} are too small } are too dangerous

All of these answer are used in models.

Explanation:

The use of models is fundamentals tool in science. Scientists used the models to observe phenomena which happen too slowly, or happen too quickly or may to large or small process and how to extent it may dangerous for firsthand. They used different model depending upon whether which type of question is investigating.

i think the answer is a and b

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