$In$ September $2011,$ more than two years after Congress and the Obama administration had enacted the $2009$ stimulus package, a poll conducted $by$ the Washington Post and ABC News found that only $17$ percent $of$ those polled thought that the "Obama economic program" was "making the economy better." Thirty$-$four percent thought $it$ was making the economy worse, and $47$ percent thought $it$ was having $no$ effect.

Source: Washington PostdashABC News Poll, "National Politicslong dashFull Trend," washingtonpost.com $,$ August $29$dashSeptember $1,2011.$

Part $2$

$a.$ How can economists judge whether the stimulus program was effective?

$A.$

Economists try $to$ determine $if$ the stimulus package pushed real $GDP$ further away from potential $GDP$ and reduced structural unemployment, but since other factors affect $GDP$ and unemployment $at$ the same time, $itis$ difficult $to$ separately identify the effectiveness $of$ the package itself.

$B.$

Economists focus $on$ determining $if$ the stimulus package was effective $at$ reducing both the inflation rate and the unemployment rate $to$ judge how effective $it$ was $in$ increasing real $GDP.$

$C.$

Economists try $to$ determine $if$ the stimulus package pushed real $GDP$ closer $to$ potential $GDP$ and reduced cyclical unemployment, but since other factors affect $GDP$ and unemployment $at$ the same time, $itis$ difficult $to$ separately identify the effectiveness $of$ the package itself.

$D.$

$Itis$ a simple matter for economists $to$ determine the effectiveness $of$ the stimulus package $by$ analyzing its effects $on$ increasing real $GDP$ and reducing cyclical unemployment.