The economic dynamism, which is the index of productive growth in dollars for countries that are designated by the World Bank as middle-income are in Table 1 ("SOCR data 2008," 2013). Countries that are considered high-income have a mean economic dynamism of 60.29. Does the data show that the mean economic dynamism of middle-income countries is less than the mean for high income countries? Why or why not? Test at the 5% level.