电流互感器的二次负荷通常用（）值表示。A、有功功率 B、无功功率 C、视在功率 D、

胰岛素剂量不足或中断可引起（）

A.低血糖反应

B.妊娠后期糖尿病

C.酮症酸中毒

D.2型糖尿病

E.血管神经性水肿

甲、乙二人正在议论郑建敏。
甲：郑建敏是福特公司如今最得力的销售经理。
乙：这怎么可能呢据我所知，郑建敏平时开的是一辆日本车。
乙的判断，包含了以下哪项假定

A．日本车现在越来越受欢迎，占领着越来越大的国际市场。

B．这辆日本车的性能一定非常优秀，才可能吸引福特公司的销售经理。

C．一个公司的销售经理应当使用本公司的产品，哪能买别的公司的车。

D．郑建敏开的那辆日本车可能是福特公司在日本的合资企业生产的。

E．最得力的销售经理应当享受最高级的待遇，所以郑建敏能买日本车。

水面下一单色光源发出的一条光线射到水面的入射角为30°，从水面上射出时的折射角是45°，求：①水的折射率；②光在水面上发生全反射的临界角．

炉顶空间温度对化学产品（）及石墨生长有直接影响。

The usual way to ensure reliable delivery is to provide the (71) with some feedback about what is happening at the other end of the line. Typically, the protocol calls for the receiver to send back special (72) frame bearing positive or negative (73) about the incoming frames. If the sender receives a positive acknowledgement about a frame, it knows the the frame has arrived safely. On the other hand, a negative acknowledgement means that something has gone wrong, and the frame must be transmitted again.
An additional complication comes from the possibility that hardware troubles may cause a frame to (74) completely. In this case, the receiver will not react at all, since it has no any reason to react. It should be clear that a protocol in which the sender transmits a frame and then waits for an acknowledgement, positive or negative, will hang forever if a frame is ever lost due to, for example, (75) hardwareo

A．data

B．control

C．request

D．session