(environmental externalities) , . (external costs), .
(tragedy of the commons) , , - , , , . , ? , ?
(perfectly elastic supply) . , . ( ), .
(free riding) , , , . - , , , .
(social costs) (. , ).
(economic instruments) , , , , , . , , , , , .
(regressive taxes) . (progressive taxes). , . , , ( , ), . .
(opportunity costs) , - . , .