Unemployment is measured by the excess of Qs over Qd at the minimum wage of Pm. Public goods are those whose benefits are non-exclusive. Everyone receives them whether they have paid for the public good or not. For example, national defense, the benefits from action to prevent depletion of the ozone layer or the melting of the polar ice caps. These explain the growth of the public sector.
Monopoly forces undermine optimal market outcomes as well.
Again public sector regulation is required. There is a trade-off between public goods and private goods . 1 meaning that consumers are very responsive to changes in price. A 1 percent rise in price will cause a 4.6 percent fall in quantity-demanded. If demand for a good is elastic then a rise in price will lower total revenue while a decrease in price will increase total revenue.