Three patients are accepted into a clinical trial for a new drug. According to the severity of the condition of each patient, the doctors estimate that the probability that the drug will be effective for Patient A is 0.7, the probability that it will be effective for Patient B is 0.2, and the probability that it will be effective for Patient C is 0.6. Assume that the success of the drug for the three patients is independent. (8 marks) a. Draw a tree diagram displaying all outcomes and joint probabilities measuring the effectiveness of the drug for all three patients