DAX Help, Table Relationships

Hi Community,

I am looking for possible solutions for the below example;

Desired 1st step:

Using Table 2 above I would like to return the difference in sales between each product for Time Scale 1 vs. Time Scale 3 

Desired 2nd step:

After creating a scatter plot using the X and Y locations in Table 1, I would to use the data retrieve in step one to "size" the dots on the scatter plot. How do I create a relationship to associate these tables and establish the correct relationship for this visual?

Any help or an example .pbix file of a similar scenario would be of great help!!