$2.(15$ marks$)($Make sure both answers be plagirism free$)$

$($a$)$ Define property rights. Discuss diagrammatically how can well$-$defined property rights

lead to social efficiency. Be sure to explain the relevant concepts that you use in your discussion.

$($b$)$ What is a market failure? Discuss market failure in the presence of externality. Compare the outcomes in the case of market failure with the socially efficient outcomes in part $($a$)$