某内河货船，为降低建造成本，在管系设计中部分管路、阀件和附件选用灰铸铁，摘要如下：

甲、乙、丙各有球若干，甲给乙的球和乙现有的球一样多，甲给丙的球和丙现有的球一样多，然后乙也按甲和丙手中的球数分别给甲、丙添球，最后丙也按甲、乙手中的球数分别给甲、乙添球，此时三人都各有球16个，开始时甲有多少球

A．26

B．24

C．32

D．30

With science and technology advancing, plentiful kinds of medicines are being developed to _____ us of our pain caused by diseaese.

A．cure

B．remove

C．relieve

D．reduce

已知一台水泵的效率η=85%，轴功率N=20Kw，扬程H=50m，试计算泵的流量。（g=9.8m/s²，р=1000kg/m³）。

Most IP layer-based proxy mechanisms, such as network address translation (NAT), only support uni-directional proxy, from the internal network to external network (the Internet). The proxy establishes the communication channel by (66) IP addresses. The IP addresses must be (67) . These proxy mechanisms prevent applications that must establish return data channels from establishing their data channels, such as, multimedia applications. IP layer-based proxy mechanisms need additional software (68) for each application that uses (69) channels. SOCKS identifies communication targets through domain names, overcoming the restriction of using private IP addresses. SOCKS can use domain names to establish communication between separate LANs, with (70) IP addresses.

A．duplicating

B．overlapping

C．crossing

D．repeating

网管及支撑系统专业管理类指标包括网管及支撑系统（）完整性，采集数据的完整性、准确性和及时性，网管及支撑系统可用性，网元接入网管及支撑系统的及时率。