Question: Shamrock Oil has some revised information concerning the accuracy of the geological test probabilities. According to this new information, the probability that the test will be positive, given that oil is present in the ground, is 0.85. The probability that the test will be negative, given that oil is not present, is 0.75. Calculate the posterior probabilities and reevaluate the decision tree from Does this new information affect Shamrock Oil's original decision?