Determine (a) the x test statistic, (b) the degrees of freedom, (c) the critical value using a = 0.05, and (d) test the Outcome A B C DC hypothesis at the a = 0.05 level of significance. Observed 9 11 11 9 Expected 10 10 10 10 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.)