已知受控系统(sum(A,b,c^T))，系数矩阵为(A=left[begin{matrix}1&0&03&-1&10&2&0end{matrix}right],b=left[begin{matrix}211end{matrix}right]，c^T=left[begin{matrix}0&0&1end{matrix}right]),设计全维状态观测器(dot{hat{x}}=(A+Mc)hat{x}+bu-Mtilde{y})，则(M)取以下何值时，能使得观测器的极点为-3、-4和-5?

TheissuingdateofadraftisMay31.Iftenorofthedraftisstatingas（1）“at90daysafterdate”，（2）“atonemonthafterdate”,thedateofpaymentwillbe（）

读程序，输出结果正确的选项是（）。intmain(void){intx=1,y=1;{inty=2;x=3;printf("x=%d,y=%d\n",x,y);}printf("x=%d,y=%d\n",x,y);return0;}

2.改革开放以来，经过近年来的发展，建筑市场的市场主体是（）。

给出下面代码：　　1:classParent{　　2:privateStringname;　　3:publicParent(){}　　4:}　　5:publicclassChildextendsParent{　　6:privateStringdepartment;　　7:publicChild(){}　　8:publicStringgetValue(){returnname;}　　9:publicstaticvoidmain(Stringarg[]){　　10:Parentp=newParent();　　11:}　　12:}　　那些行将引起错误？()

类Test1定义如下：1.publicclassTest1{2．publicfloataMethod(floata,floatb){}3．4．}将以下哪种方法插入行3是不合法的。（）

以下程序运行后的输出结果是（）intmain(){inta=1,b=2;a=a+b;b=a-b;a=a-b;printf("%d,%d\n",a,b);return0;}

1.TheworldisquicklyrealizinghowmuchitdependsonChina.2.Appleisreroutingsupplychains.Ikeaisclosingitsstoresandpayingstaffmemberstostayhome.Starbucksiswarningofafinancialblow.FordandToyotawillidlesomeoftheirvastChineseassemblyplantsforanextraweek.3.Themysteriouscoronavirushasvirtuallyshutdownoneoftheworld’smostimportantgrowthengines.Desperatetoslowthefast-movingvirus,theChineseauthoritieshaveextendedthecountry’snationalholiday,andcrippledland,railandairtransport.Entirecitieshaveshutdown.4.Thefullextentofthehittothebroaderbusinessworldisnotyetclear.“Ourmembersaredealingwithvaryingdegreesofdisruptionintheirbusinesses,”saidJakeParker,theseniorvicepresidentoftheUS-ChinaBusinessCouncil.5.Iftravelrestrictionsandquarantinesareexpandedortheholidayextendedfurther,hesaid,“thatwillamplifytheseproblems.”Question:Whichofthefollowingcanbestreplace"virtually"in"Themysteriouscoronavirushasvirtuallyshutdownoneoftheworld’smostimportantgrowthengines"?

1.TheworldisquicklyrealizinghowmuchitdependsonChina.2.Appleisreroutingsupplychains.Ikeaisclosingitsstoresandpayingstaffmemberstostayhome.Starbucksiswarningofafinancialblow.FordandToyotawillidlesomeoftheirvastChineseassemblyplantsforanextraweek.3.Themysteriouscoronavirushasvirtuallyshutdownoneoftheworld’smostimportantgrowthengines.Desperatetoslowthefast-movingvirus,theChineseauthoritieshaveextendedthecountry’snationalholiday,andcrippledland,railandairtransport.Entirecitieshaveshutdown.4.Thefullextentofthehittothebroaderbusinessworldisnotyetclear.“Ourmembersaredealingwithvaryingdegreesofdisruptionintheirbusinesses,”saidJakeParker,theseniorvicepresidentoftheUS-ChinaBusinessCouncil.5.Iftravelrestrictionsandquarantinesareexpandedortheholidayextendedfurther,hesaid,“thatwillamplifytheseproblems.”Question:whichofthefollowingsentenceshastheword"idle"withthesamemeaningandusageasthatin"FordandToyotawillidlesomeoftheirvastChineseassemblyplants?"

下面代码的输出结果是（）。print(round(0.1+0.2,1)==0.3)ATrueB0C1DFalse

表达“从一个关系的所有行中提取出满足某些条件的行”，“从一个关系的所有列中提取出某些列”“提取出属于一个关系但不属于另一关系的所有元组”“将两个关系必须按照某种条件串接成一个较大的关系”的操作依次是（）。1、并2、交3、积4、选择5、投影6、差7、连接

执行下列语句后a的值为（）inta＝5,b＝6,w＝1,x＝2,y＝3,z＝4;(a＝w>x)&&(b＝y>z);

类Test1定义如下：1.publicclassTest1{2．publicfloataMethod(floata,floatb){}3．4．}将以下哪种方法插入行3是不合法的。（）

给出下面代码：　　1:classParent{　　2:privateStringname;　　3:publicParent(){}　　4:}　　5:publicclassChildextendsParent{　　6:privateStringdepartment;　　7:publicChild(){}　　8:publicStringgetValue(){returnname;}　　9:publicstaticvoidmain(Stringarg[]){　　10:Parentp=newParent();　　11:}　　12:}　　那些行将引起错误？()

以下程序的输出结果是（）main(){intx＝2,y＝－1,z＝2;if(x<y)if(y<0)z＝0;elsez+＝1;printf(“%d\n”,z)}