In March 2009, 100 registered voters were asked to rate the "effectiveness" of President Obama. In March 2010, these same people were again asked to make the same assessment. Seventy percent of the second ratings were lower than the first ratings and 30% were higher.

a. Using the sign test, specify the competing hypotheses to determine whether the President's rating has significantly declined.

b. Calculate the value of the test statistic.

c. Calculate the p-value.

d. At the 5% significance level, do the data suggest that the President's rating has significantly declined?