b4a074dfba807022ab51e42105a816ff991ab55dbaff46a49361079a27b54119 hatrack4 https://gravatar.com/hatrack4 hatrack4 https://1.gravatar.com/avatar/b4a074dfba807022ab51e42105a816ff991ab55dbaff46a49361079a27b54119 https://0.gravatar.com/avatar/4190afee0985bcfcae72d974efdb2476 thumbnail hatrack4 Mark Rackley is a retired training manager, safety director, and quality manager. He has a masters degree in engineering , emphasis in chemical engineering. Mark, an ordained elder, has taught Sunday school for years, writing some of the study materials. Pennsylvania, USA