This is the thought of the United States author in Houston and the Chinese student for eight years. Can you feel that the income of $50,000 a year allow you and your family to live in comfort? This may not be sufficient in most places. But this is indeed the middle-year income of the middle class in the United States. In the alternative, 50 per cent of Americans earn less. However, the situation is different for each State, with different living standards, and the biggest gap between the Stat...