In data communication, data link is those parts of two data terminal equipments that are controlled by a protocol along with the (71) data circuit, which together enable data (72) . So-called protocol means, in short, a set of rules that determines the behavior of functional units in achieving communication.
Data circuit, however, consists of a pair of (73) transmission channels that provides a means of two-way data transmission. Between data switching exchanges, the data circuit may or may not include data circuit-terminating equipment (DCE), depending on the type of (74) used at the data switching exchange. Between a data station and a data switching exchange or data concentrator, the data circuit includes the DCE at the data station end, and may include equipment (75) to a DCE at the data switching exchange or dam concentrator location.

A:transfer B:transmission C:passing D:delivery

In data communication, data link is those parts of two data terminal equipments that are controlled by a protocol along with the (71) data circuit, which together enable data (72) . So-called protocol means, in short, a set of rules that determines the behavior of functional units in achieving communication.
Data circuit, however, consists of a pair of (73) transmission channels that provides a means of two-way data transmission. Between data switching exchanges, the data circuit may or may not include data circuit-terminating equipment (DCE), depending on the type of (74) used at the data switching exchange. Between a data station and a data switching exchange or data concentrator, the data circuit includes the DCE at the data station end, and may include equipment (75) to a DCE at the data switching exchange or dam concentrator location.

A:handshaking B:interconnecting C:linkage D:joining

In data communication, data link is those parts of two data terminal equipments that are controlled by a protocol along with the (71) data circuit, which together enable data (72) . So-called protocol means, in short, a set of rules that determines the behavior of functional units in achieving communication.
Data circuit, however, consists of a pair of (73) transmission channels that provides a means of two-way data transmission. Between data switching exchanges, the data circuit may or may not include data circuit-terminating equipment (DCE), depending on the type of (74) used at the data switching exchange. Between a data station and a data switching exchange or data concentrator, the data circuit includes the DCE at the data station end, and may include equipment (75) to a DCE at the data switching exchange or dam concentrator location.

A:correspondent B:comparable C:similar D:analogous

若要对Data类中重载的加法运算符成员函数进行声明，下列选项中正确的是______。

A:Data+(Data); B:Data operator+(Data); C:Data+operator(Data); D:operator+(Data,Data);

设有定义：
struct complex
int real, unreal; data1=1, 8, data2;
则以下赋值语句中错误的是（）

A:data2=data1; B:data2=(2, 6); C:data2. real=data1. real; D:data2. real=data1. unreal;

若要对Date类中重载的加法运算符成员函数进行声明，下列选项中正确的是( )。

A:Data+(Data)； B:Data operator+(Data)； C:Data+operator(Data)； D:operator+(Data.Data)；

设有定义： Struct complex {int real，unreal；}data1={1，8}，data2； 则以下赋值语句中错误的是( )。

A:data2={data1.rea1，data1.unrea1}； B:data2=(2，6)； C:data2.rea1=data1-＞rea1； D:data2-＞rea1=data1.unrea1；

设有如下定义： struct complex {int real, unreal;} data1={1, 8}. data2; 则以下赋值语句中错误的是

A:data2=data1; B:data2=(2, 6); C:data2.real=data1.real; D:data2.real=data1.unreal;

若要对Data类中重载的加法运算符成员函数进行声明，下列选项中正确的是

A:Data+(Data); B:Data operator+(Data); C:Data+operator(Data); D:operator+(Data,Data);