单项选择题 16. Unemployment would cause an economy to a. produce inside its production possibilities frontier. b. produce on its production possibilities frontier. c. produce outside its production possibilities frontier. d. experience an inward shift of its production possibilities frontier. A、aB、bC、cD、d

单项选择题 2. Brenda is an excellent baker and Floyd has a plentiful farm. If Floyd trades eggs and butter to Brenda for some of Brenda’s bread and pastries,

单项选择题 四级计划编制是由项目部的（）开始编制总进度计划