Let's say you want to advertise online for a product, for example, to take an example a new chocolate bar.
I was wondering, when you want to advertise for a this product online between google ads, facebook, instagram, ....
How can you estimate the ROI and prioritize advertisements ?
Let's say you want to catch more children public. How can you say, ok with 10000$ we will cover a region, a state ?
Are you experimenting to find the right balance ?