Ashton university creates a 10-digits student number as the university enrolls each student. the first two characters must be a digit from 1 to 9. the next seven characters can be anything and the last digit just can not be the same as the ninth character. how many student numbers are possible

If f(x)=3x+1 and f^-1=x-1/3, then f^-1(7)=

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.

Jane’s favorite fruit punch consists of pear, pineapple, and plum juices in the ratio 5: 2: 3. chapter reference how much punch can she make if she has only 6 cups of plum juice?