The pdf files for practice tests are typically uploaded the day before the test. The practice tests are designed for you to find out if you have mastered the material in a chapter the day before the test is given. Instructors will not answer any questions about practice tests until the day of the actual test. That day an answer key will be posted and tutors will be available. It makes no sense for the teacher to show you how to do the test since they are not the ones taking the tests. They are designed for you to do on your own!