An increase in transfer payments would have the same short run effect on the government deficit as an equal

Explain at least three ways that self-interest can motivate a selfless act.

What will be an ideal response?

Everyone in the neighborhood has been complaining about the deteriorating condition of the park, but nobody has cleaned it up. Why not?

A. No single person's benefit from cleaning the park exceeds that person's cost of cleaning it. B. There is an excess demand for parks in the neighborhood. C. There is an excess supply of parks in the neighborhood. D. The social benefit of cleaning the park exceeds the social cost of cleaning it.