2. In lecture we discussed air pollution as a 'commons tragedy'that qualifies it for action (intervention) by government. a. What are the two key characteristics of a common-property resource? b. The regulatory approach to air quality regulation involves the use of 'standards'. An important 'ambient air-quality standard' set by the central government is the PM1o standard: in any 24-hour period the average concentration of PM1D in the air should not be more than so pgln's (PM1o refers to particulate matter of less than 10 pm- that's 10 micrometres, or 1l1ooth of a millimetre - in diameter, so pretty small). Any concentration greater than 50 pglma is deemed hazardous to health. The data below show the hourly concentration of PM1o over the course of a typical winter day in Alexandra. d PM" Valuo lrncglm') 338883888 .5 a I: I II I C 7 I s1011uuuuunuuunnzsu Wanna\" What do the data suggest about health hazard? Why does the concentration vary over the day? Would Alexandra be "out of compliance" with the PM1o standard? Evaluate the ambient standard as a tool for environmental monitoring