Identify each described physical separation technique. A liquid is carefully poured out, leaving the solid behind in the container. Choose... A solid is caught on paper or a membrane while the liquid passes through. Choose... A solid mixture is heated. One component transitions directly between solid and gas. Choose... A solvent is added to dissolve only one mixture component and then the liquids are separated.

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.

i just calculated it all out, and not including weekends, and all the different days off. as of this school year (2018-2019) students are spending 2198 hours in school this year

what is the question here. i think you messed up.