$(25$p$)$ Use the data in MURDER.DTA for this exercise. The variable mrdrte is the murder

rate; that is$,$ the number of murders per $100,000$ people. The variable exec is the total number

of prisoners executed for the current and prior two years; unem is the state unemployment

rate.

$($a$)(5$p$)$ How many states executed at least one prisoner in $1991,1992,$ or $1993?$ Which

state had the most executions?

$($b$)(5$p$)$ Using the two years $1990$ and $1993,$ do a pooled regression of mrdrte on d$93,$

exec, and unem. What do you make of the coefficient on exec?

$($c$)(5$p$)$ Using the changes from $1990$ to $1993$ only $($for a total of $51$ observations$),$

estimate the equation by OLS and report the results in the usual form. Now, does

capital punishment appear to have a deterrent effect?