There are three main methods to reduce emissions. These are emission standards, emission fees and trading emission permits. (40) imply a quantity control orer emission lerels. Howerer, they can not take into account the idea that some fimms may have different (41). (42), on the other hand, present clarity regarding the cost of abatement. But the amount of emission (43). This abated remains uncertain. Alternative is to leare the emission abatement process to the includes the introduction of _(44). 40. a) Emission standards c) Emission fees b) Marginal costs of abatement d) Tradable emission pemits 41. a) Emission standards c) Emission fees b) Marginal costs of abatement d) Tradable emission pemits 42. a) Emission standards c) Emission fees b) Marginal costs of abatement d) Tradable emission penmits 43. a) market b) government c) firms d) United Nations 44. a) Emission standards c) Emission fees b) Marginal costs of abatement d) Tradable emission permits