WASHINGTON -- At least 28 senior-level federal employees in eight agencies have bogus college degrees, including three managers at the office that oversees nuclear weapons safety, congressional investigators have found. The problem is likely even bigger, mainly because the government has no uniform way to check whether employees' alma maters are ``diploma mills'' that require little, if any, academic work, the General Accounting Office reported. The findings by the investigative arm of Congress were to be presented to a Senate committee Tuesday. An earlier GAO report revealed how easy it is to buy a degree from a diploma mill; this...