用以观察细菌内部超微结构的最好仪器是
A．相差显微镜
B．光学显微镜
C．荧光显微镜
D．电子显微镜
E．暗视野显微镜
参考答案：D
适于外阴炎局部治疗的是 （）
A.3%硼酸液湿敷
B.40%氧化锌油膏涂于局部
C.呋喃西林会阴擦洗
D.1：5000高锰酸钾坐浴
E.生理盐水 * * 灌洗
When market rates were 6 percent an analyst observed a $1000 par value callable bond selling for $ 950. At the same time the analyst also observed an identical non-callable bond selling for $ 980. What would the analyst estimate the value of the call option on the callable bond to be worth
A．
B．
C．
