36 - [( 3 + 13) divided by 4] and {9 + [( 15 - 7) x 3]} divided by 3

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.

Which of the following is not a subset of {1,2,3}?

1. suppose that scores on a knowledge test are normally distributed with a mean of 71 and a standard deviation of 6. a. label the curve: show the mean and the value at each standard deviation: b. if angelica scored a 76 on the test, what is her z-score? (draw her score on the curve above and label) c. what percent of students did angelica score higher than? how can you tell? d. if 185 students took the test, how many students scored higher than angelica?