Marla is trying to decide whether she should apply for a one-year diploma or not. It will cost her $10,000 in tuition. After she gets the diploma, she will earn $2000 more than her current income per year for her working life. Marla plans to work for 25 more years. If her discount rate is 10%, what is the NPV of investing in the diploma? Will Marla take the diploma course? At what discount rate would Marla be indifferent between joining and not joining?