Carbon dioxide emissions have been linked to increased air pollution. The following table lists some possible public policies aimed at reducing the amount of carbon dioxide in the air.

For each policy listed, identify whether it is a command-and-control policy (regulation), tradable permit system, corrective subsidy, or corrective tax.

Public Policy	Command-and-Control Policy	Tradable Permit System	Corrective Subsidy	Corrective Tax
The government orders every factory to adopt a new technology, which reduces carbon-dioxide emissions into the atmosphere.
The government agrees to reimburse all factories that purchase new, emissions-reducing technology in order to provide cleaner air.
The government charges factories $170 for every ton of carbon dioxide they emit.
The government limits total carbon-dioxide emissions by all factories to 140,000 tons per year. Each individual factory is given the right to emit 120 tons of carbon dioxide, and factories may buy and sell these rights in a marketplace.