What is the simplified form of this question

The bike store marks up the wholesale cost of all the bikes they sell by 30% and andre wants to buy a bike that has a price tag of 125 what was the wholesale cost of the bike

Explain how you can use the associative property to evaluate (7x50)x4.

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.