The temp was 20 degree. it dropper 31 degree by the end of the day . what was the temperature at the end of the day

For the equations below which statement is true ?

What is the measure of angle tvu shown in the diagram below

Ascientist wants to use a model to present the results of his detailed scientific investigation. why would a model be useful? a )because the model makes the concepts easier to understand b) because the model is easy to put together and to use c) because the model prevents other scientists from asking questions d) because the model requires the audience to pay full attention to it i don't know what to choose because between a and d a is much more likely than d because it only wants to get the attention of the audience. i'm confuse.