【简答题】假定某经济社会的消费函数C=300+0.8Yd、投资I=200、税收函数T=0.2Y(单位:亿美元),试求:
【单选题】下列各组辅音声母中都属于舌尖前音的是( )。
【单选题】Making mistakes is a part of learning. By pointing out your errors and _____ you correct them, a teacher is teaching you. [ ]
【单选题】Studying and observing before making a choice will avoid making errors.
【判断题】Studying and observing before making a choice will avoid making errors.