David has been working at a local department store since graduating from high school six years ago. He currently earned $$38000$ per year. David really likes working in the retail industry. He knows, however, that he will need to earn a four$-$year college degree in order to obtain a manager position. After doing online research David is determined that the total cost associated with obtaining a business group at a local college will be $$116000.$ what is the payback period on David's potential college investment if you can expect earn $$48,300$ annually as retail store manager