If your weekly salary is 1015.00 how much do you have left each week after you pay the following

If 20% of a number is 35, what is 50% of that number?

On saturday a souvenir shop had 125 customers. sixty four percent of the costumers paid with a credit card. how many costumers paid with cash?

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.