This learning guide is a self-instructional packet for one task identified as essential for performance on an entry-level job in parts marketing. The guide is based on a terminal performance objective (task) and two enabling objectives. For each enabling objective, some or all of these materials may be presented: learning steps (outline of student activities) with necessary resources/materials cited, instruction sheet(s), and self-check with answer key. Either a performance test or, more seldom, a written test (with answer key) concludes each guide. The task covered in this guide is figuring sales tax. (YLB)