An athlete has tested positive for steroids. A false positive means the test was positive, but the athlete did not use steroids. A true positive means the athlete tested positive and used steroids. What is the probability the athlete used steroids, given that 1% of athletes use steroids, the test's faise positive rate is 0.5%, and the test's true positive rate is 99%? 2.0% 99.9% 66.7% 1.0% 0000