美国历史 Comparing the effects of the Civil War on American national identity | US history | Khan Academy
美国历史 Immigration and migration in the Gilded Age | Period 6: 1865-1898 | AP US History | Khan Academy
存著再看年 06:49 会员 Production Possibilities Curve as a model of a country’s economy | AP Macroeconomics | Khan Academy
存著再看年 06:16 会员 Changes in equilibrium price and quantity when supply and demand change | Khan Academy
存著再看年 06:15 会员 Change in supply versus change in quantity supplied | AP Macroeconomics | Khan Academy
存著再看年 08:27 会员 Change in demand versus change in quantity demanded | AP Macroeconomics | Khan Academy
存著再看年 08:51 会员 Input approach to determining comparative advantage | AP Macroeconomics | Khan Academy
存著再看年 09:55 会员 Opportunity cost and comparative advantage using an output table | AP Macroeconomics | Khan Academy
存著再看年 05:25 会员 PPCs for increasing, decreasing and constant opportunity cost | AP Macroeconomics | Khan Academy
存著再看年 06:50 会员 When there aren’t gains from trade | Basic economics concepts | AP Macroeconomics | Khan Academy
存著再看年 09:44 会员 Command and market economies | Basic economics concepts | AP Macroeconomics | Khan Academy
存著再看年 05:00 会员 Normative and positive statements | Basic economics concepts | AP Macroeconomics | Khan Academy
存著再看年 06:50 会员 Economic models | Basic economics concepts | AP Macroeconomics and Microeconomics | Khan Academy
