Follow my in sta: bestiestu pid (no space)
drop ur in sta :

ok your anser is 56^92

Explanation:

tracks, burrows, eggshells, nests, tooth marks, or gastroliths

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.