Determine (a) the x2 test statistic, (b) the degrees of freedom, (c) the critical value using a = 0.05, and (d) test the hypothesis at the = 0.05 level of significance. Ho PA PB PC PD=4 H: At least one of the proportions is different from the others. (a) The test statistic is (Type an exact answer.) Outcome Observed Expected A B C D 96 111 89 104 100 100 100 100