Lord Du Raq owns a crumbling castle in Scotland. The revenue from visitors is no longer sufficient to cover the upkeep of the property and he must decide what to do. A national heritage organization has offered to buy the property for £8m. Alternatively he could have a theme park constructed in the grounds. If this proves to be a success he will make a profit of £25m, but if it is not he will incur a loss of £5m. He estimates that the chance of success in the venture will be 0.6. He could start building the theme park right away, but a tourist authority contact has suggested that before he decides whether or not to build the park he should hire Baz Umney, an expert on leisure developments, to assess the prospects of the venture. Baz has a distinguished record, accurately predicting the success of similar ventures 70% of the time and accurately predicting the failure 80% of the time. Create a decision tree to model the situation Lord Du Raq faces and, using Bayes' rule, suggest what he should do.