Associated Press: Envoys from India, China and other developing nations offered Wednesday to hold the line on their greenhouse gas emissions, but only as measured against the per-capita pollution produced by the United States and other richer nations. The U.S. emits about 7 billion metric tons of carbon dioxide and other greenhouse gases a year. China, with 1.3 billion people, has pulled roughly even with that amount, but its emissions per person are roughly one-fourth that in the U.S., which is home …