An experiment was conducted to determine whether the injection of antibodies reduced the probability of infection, by examining the records of 140 patients. It was found that 16 of 140 patients that took part in the experiment had transfusion - transmitted infection. Of these 16 patients, 5 patients were injected with antibodies. A total of 79 patients from those who took part in the experiment were injected with antibodies. The data obtained in the experiment should be summarized in the contingency table below. Using information given above fill in the contingency table below. Is there sufficient sample evidence to indicate that the occurrence of transfusion - transmitted infection is independent of the injections of antibodies? Test appropriate hypotheses using level of significance a = 0.05. Presence of infection Yes No Injection of antibodies Yes No a. Place the values of observed frequencies; row, column and overall totals; and expected frequencies into the table. Leave two digits after decimal point in the expressions for expected frequencies. (1 mark). b. State null and alternative hypotheses. (1 mark) Ho: H: c. State the calculated value of test statistic. (1 mark) Xobs, = d. State the critical value of test. (1 mark) Xor. = e. Decide whether null hypothesis is true and make the conclusions