Depict a market for investment services. In the same diagram, illustrate an efficient effect on the market for investment services if the government requires an occupational license to provide personal investment advice. (Hint: For an efficient result, the regulation must result in an increase in quantity exchanged.)

3B(a). Depict the market for water located in an adjacent lake used as the local water supply that it is polluted by refrigerator production. Assume that the quantity of water is fixed, and that the local city must filter the water before it is provided to households. In the same diagram, illustrate the effect on the market for drinking water from pollution.

3B(b). Reproduce your diagram from 3B(a). Illustrate the effect in the market for water if the government imposes regulations on refrigerator production to limit environmental pollution. Identify the new supply curve with subscript "3".