夏普指数是1966年由夏普提出的,它以证券市场线为基准,指数值等于证券组合的风险溢价除以标准差。()
参考答案:错
常用于养殖场作动物用具消毒的药物包括()
A.2%氢氧化钠
B.5%苯扎溴铵
C.0.3%过氧乙酸
D.1%次氯酸钠
E.1%甲醛
---Emma has to stay at home to look after her little sister, ?
---Yes, because her mother has gone to the supermarket.
A.does she
B.is she
C.doesn’t she
D.hasn’t she