9. A student obtains marks in mathematics, physics, and biology. The average of his mathematics and physics marks is 15, his average mark for mathematics and biology is 17, and his average mark for physics and biology is 23. If so, what mark does the student obtain from biology?

Ineed ! the person who answers and shows their work on they got the answer first will be marked the !

The bake stars picked 907 apples last weekend at a local orchard they made caramel apples and sold them in the bakery in trays of 6

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.