Vitamins A, D, E, and K are fat-soluble. B vitamins and vitamin C, on the other hand, are water-soluble. Vitamin A. Vitamin A is found in many yellow-colored fruits and vegetables. Good sources include: sweet potatoes; winter squash; carrots; dark leafy-green vegetables; fatty animal tissue, such as liver or fish
A negative externality (also called external cost or external diseconomy) is an economic activity that imposes a negative effect on an unrelated third party. It can arise either during the production or the consumption of a good or service.
Network externalities is the situation where the usefulness of a product increases with the number of. consumers who use it. Some economists argue that network externalities can serve as barriers to entry, but there is considerable debate about the extent to which they serve as barriers. D. Natural Monopoly.