How to complete a ratio table and convert the ratio to percentage

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.

If sr is 4.5cm and tr is 3cm, what is the measure in degrees of angle s? a. 56.3 b. 33.7 c. 41.8 d. 48.2

Julie multiplies 6.27 by 7 and claims the product is 438.9 .explain without multiplying how you know juliesanswer is not correct.find the correct answer