The postal service charges $2 to ship packages up to 5 ounces in weight and $0.20 for each additional ounce up to 20 ounces. After that they
charge $0.15 for each additional ounce.
What is the domain of this relation?

The postal service charges 2 to ship packages up to 5 ounces in weight and 020 for each additional ounce up to 20 ounces After that they charge 015 for each add class=