Answers
ANS 1
Option D. Both B and C , A pure public good is a good which has no rival also its consumption is not subject to exclusion , an example can be take of street light, its consumption cannot be avoided if one is travelling in streets and also its consumption does not affect other people.
ANS 2
Option B. positive and decreasing , as the public goods are used by the public and the usage of one unit doesnt effect the quantity available for the other people due to which the marginal cost decreases constantly with every other usage and is never negative.
ANS 3
Option B . benefits enjoyed by existing consumers are unaffected as more consumers enjoy a given quantity of the good. It means that the good's quantitry is not affected by the consumption of any person, like the consumption of street light doesnt affect the consumption of other people.
ANS 4
Option A.
The marginal benefit obtained by each consumer equals the marginal social cost of producing the good., The public goods include the marginal cost of externalities too and the point where marginal social benefit matches the the marginal cost , it is the point of efficient output.
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