The Mayon Clinic gets medical supplies delivered from two sources, Medex and ProMed. There is a probability of 60 percent that the order consists of medical supplies from Medex. According to the case, 20 percent of all medical supplies produced at Medex are defective and only 10 percent of the medical supplies from ProMed are defective.

 a. Construct a probability tree for this problem. 

b. Construct a probability table for this problem. 

c. Find the probability that the medical supplies come from Medex and are defective.

 d. Given that you have a defective medical supply, what is the probability that it came from ProMed?

Please provide the answers in excel and provide an explanation with formulas