在土料防渗的技术要点中,确定防渗层厚度,根据不同土料种类,渠底厚度10~40cm,渠坡厚度为()cm。
A、20
B、30
C、40
D、100
参考答案:A, B, C
Peter's father asked him to spend his time on something________researching into instead of playing all the time.[ ]
A. worthy
B. valuable
C. worth
D. precious
投资者通过深圳证券交易所交易系统认购上市开放式基金的,必须按照金额进行认购,即投资者的认购申报以元为单位。()