A real estate agent who focuses on low value homes is interested in using decision trees to classify the values of homes in this area. He considers misclassifying a 'low' value home as 'high' to be a more costly error, because it will be harder for him to sell an actual 'low' value home if he presents the 'false high' results to the seller. Therefore, he assigns a cost of 0.9 to such an error (and thus 0.1 for the cost of misclassifying a 'high' value home as 'low'). With this set of costs, which tree model is better for him? Show your calculations.