A decrease in which of the following would decrease the tax wedge?

Supplier Power Nora's Nicest Knick Knacks has produces a variety of products sold as souvenirs. She started out printing local sayings on tee-shirts, e.g., FDNY, and purchased plain tee-shirts from a single supplier. Since then, she has added coffee

mugs, key chains, souvenirs spoons and many other items. For each of these, she has lined up one or more suppliers. How does the change in the sourcing of her inputs affect how much of the value she creates that she gets to capture?

What characteristics distinguish private goods from public goods?