关于x、y的方程组x+m=6y-3=m中，x+y=______．

输油管道连接时，除与设备及其附件连接处采用法兰联接外，其余均采用焊接连接。( )

现有浓度均为0.1 mol·L^－1的下列溶液：

①硫酸；②醋酸溶液；③氢氧化钠溶液；④氯化铵溶液；⑤醋酸铵溶液；⑥硫酸铵溶液；⑦硫酸氢铵溶液；⑧氨水。请回答下列问题：

(1)①、②、③、④四种溶液中由水电离出的H^＋浓度由大到小的顺序是(填序号)________。

(2)④、⑤、⑦、⑧四种溶液中NH₄^＋浓度由大到小的顺序是(填序号)________。

(3)将③和④等体积混合后，混合液中各离子浓度关系正确的是________。

A．c(Na^＋)＝c(Cl^－)＞c(OH^－)＞c(NH₄^＋)

B．c(Na^＋)＝0.1 mol·L^－1

C．c(Na^＋)＋c(NH₄^＋)＝c(Cl^－)＋c(OH^－)

D．c(H^＋)＞c(OH^－)

下列建设工程项目进度控制措施中，属于管理措施的有（）。

A.选择合同结构

B.分析工程风险

C.建立管理组织体系

D.确定物资采购模式

E.明确管理职能

超短波不能用于（）

A.心前区

B.眼部

C.生殖腺

D.有金属物的部位

E.头部

Rapid advances in computer and communication technologies have resulted in the (58) merger of these two fields. The lines have bluned among computing, switching, and digital transmission equipment, and the same digital techniques are being used for data, voice, and image transmission. Merging and evolving technologies, coupled with increasing demands for efficient and timely collection, processing, and (59) of information, are leading to the development of (60) that transmit and process all types of data. The ultimate goal of this evolution is something its proponents-some of the most powerful forces in the computing and telecommunications industries-call the (61) .The (61) will be a worldwide public telecommunications network that will deliver a wide variety of services. The (61) will be defined by the standardization of user interfaces, and will be implemented as a set of digital switches and paths supporting a broad range of traffic types and providing (62) processing services. Inpractice, there will be multiple networks, implemented within national boundaries, but from the user’s point of view there will be a single, uniformly accessible worldwide network.

Rapid advances in computer and communication technologies have resulted in the（）merger of these two fields.

A．decreasing

B．increasing

C．collective

D．single