If the 95% confidence interval for the difference in means between two groups is (0.02, 0.21), at the 5% significance level, we couldn't make a conclusion about the null hypothesis of equal means because we don't know whether the two-sided p-value is greater or less than 5%. we would reject the null hypothesis of equal means because the two-sided p-value is less than 5%. we would not reject the null hypothesis of equal means because the two-sided p-value is less than 5%. we would reject the null hypothesis of equal means because the two-sided p-value is more than 5%