一个幼儿园大班有50名小朋友。班里有各种玩具155件，把这些玩具分给小朋友。是否

电容器组在额定电压下进行3次冲击合闸试验，熔丝不应熔断，各相电流之差不超过（）。

A.3%

B.5%

C.7%

D.10%

点（3，-2）先向右平移2个单位，再向上平移4个单位，所得的点关于以y轴为对称点的坐标为______．

Following a year of fast development, by the first quarter of this year, China has had about 1,100 e-commerce websites .

A．China had about 1,100 e-commerce websites by the end of last March

B．by the end of the first quarter of this year, China has had about 1,100 e-commerce websites

C．by the end of this recent past March, China has about 1,100 e-commerce websites

D．by the end of this first quarter, China had about 1,100 or so e-commerce websites

消防一级网中，消防站固定台是全网主台。（）

芦荟药材原植物属于（）

A.爵床科

B.豆科

C.茜草科

D.漆树科

E.百合科