A survey asked Democrats, Republicans, and independent voters what the most important message is to send to Congress.

A survey asked Democrats, Republicans, and independent voters what the most important message is to send to Congress. The most popular response for all three groups was to "focus on the economy." The number of respondents, the messages they want sent, and their party affiliations are shown in the accompanying table.

a. Using a = 0.05, perform a chi-square test to determine if the proportion of voters who responded "focus on the economy" differs among the three groups of voters.