Answer:
d) 3 units and the socially optimal quantity supplied will be 3 units
Explanation:
A public good is a good that is non excludable and non rivalled in consumption. This means that the use by a person does not reduce availability to others.
Willingness to pay is the highest amount a person is willing to pay.
If the collective willingness to pay is $6, then demand would be 3, because it is at this quantity that total willingness to pay equals $3.
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