委托买卖是证券经纪商的主要业务。( )
参考答案:对
解析: 委托买卖是指证券经纪商接受投资者委托,代理投资者买卖证券,从中收取佣金的交易行为,这是证券经纪商的主要业务。
Yesterday if the policeman _______earlier, the fight between the two boys would have been prevented.
A.would have arrived
B.had arrived
C.were to arrive
D.arrived
下述哪种情况不宜作为葡萄胎预防性化疗的条件?()
A.年龄大于40岁
B.β-HCG大于100KIU/L
C.黄素化囊肿大于6cm
D.无条件随访
E.部分性葡萄胎