下列说法中,错误的是( )
A.氧气可用于潜水、医疗急救
B.二氧化碳能支持燃烧,可作燃料
C.氮气充入食品包装袋内可以防腐
D.稀有气体充入灯泡中可使其耐用
答案:B
_____ you read the instructions closely, you would know what I _____ referring to now. [ ]
A. Had; was
B. Should; am
C. Had; am
D. If; was
理性预期学派认为在短期中可以通过宏观经济政策解决失业问题。