UNITED NATIONS (AP) - The United Nations is studying whether it was appropriate for the top U.N. envoy for North Korea to maintain business ties with a South Korean businessman accused of wrongdoing in the U.N. oil-for-food scandal, U.N. officials said Tuesday. U.N. Secretary-General Kofi Annan said he had not known about the ties between Maurice Strong and Tongsun Park, a native of North Korea and citizen of South Korea who was also accused in the 1970s of trying to buy influence in Congress. Strong is the U.N. point man on stalled six-nation talks aimed at persuading North Korea to...