1. what are some similarities between the dogs pictured? what are some differences? . 2. what are some ways you can divide these dogs into groups? 3. how could you improve your dichotomous key? 4. why is it important to classify things?

answer : a model is often used to explain and make things easier to understand when any scientific topic needs to be demonstrated and explained.

as in this case where a scientist wants to use a model to present the results of his detailed scientific investigation. he should do it as it will him to make the audience understand the concept in a much better way. also, it can be changed according to new scientific understandings.