For the store on my website, I am trying to make it so that every item in the cart gets charged for the shipping fee. For example, on my site, I have a product for $30. The domestic USA shipping fee is $3. I want it so that if only one is added to the cart, 30 + 3 is charged. If two are added, it will be 30 + 30 + 6. If three are added, it will be 30 + 30 + 30 + 9. Each item is responsible for its own shipping price.