Laurie Seals and Julie Winn are roommate at Upland State College. Lauri majors in political science and JUlie is an accounting major. Recently, one of Lauire's political science classes has been disscussing the impact of derivative tradign losses on the finances of several public institutions in the United State, including city governments and public colleges. The political science class has decided that derivatives are nothing more than a sophisticated form of gamvbling and that their trading in the United States should be banned, How show Julie explain to Laurie that derivatives serve a vital business purpose?