Think about the differences between Earth and the moon. Then
make a plan for a settlement on the
moon. Explain what settlers will need
to take to the moon or change on the
moon to make it suitable for life.

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.

the answer is 303.15 or 303