当两电阻R1=20Ω，R2=30Ω并联时，其总电阻为（）。A、50ΩB、30ΩC、20ΩD、12Ω
当两电阻R1=20Ω，R2=30Ω并联时，其总电阻为（）。
- A、50Ω
- B、30Ω
- C、20Ω
- D、12Ω
相关考题：
以下程序用来输出20个在开区间(10,87)上的随机整数数R,每行输出4个整数。请完成空白处.Private Sub Commandl. Click( )For I=1 To 10R = Int (Rnd * 76 + 11)Print R;If【 】Then PrintNext IEnd Sub
在窗体中添加一个名称为Command1的命令按钮，然后编写如下程序： Public x As Integer Private Sub Command1_Click() x=10 Call s1 Call s2 MSgBox x End Sub Private Sub s1() x=x＋20 End Sub Private Sub s2() Dim x As Integer x=X＋20 End Sub 窗体打开运行后，单击命令按钮，则消息框的输出结果为______。A．10B．30C．40D．50
当执行以下过程时，在名为lblResult的标签框内将显示______。Private Sub Command1_ Click() Dim I, R R = 0 for I = 1 To 5 step 1 R= R+ I Next I lblResult. Caption = Str＄(R)End SubA．字符串15B．整数15C．字符串5D．整数5
在窗体中添加一个标签LblResult和一个命令按钮Command1，然后编写程序。程序的功能是单击命令按钮，计算1+2+3+4+5的值，并把结果转化为字符串显示在标签内，能够实现上述功能的程序段是， ( )A．Private Sub Command1_Click() Dim I,R As Integer For I=1 To 5 Step 1 R=R+I Next LblResult. Name=Str$ (R) End SubB．Private Sub Command1_ClickO Dim I,R As Integer For I=1 To 5 Step 1 R=R+I Next LblResult. Caption= Str$ (R) End SubC．Private Sub Command1_Click() Dim I,R As Integer Do While I＜5 R=R+I I=I+1 Loop LblResult. Caption=Str$ (R) End SubD．Private Sub Command1_Click() Dim I,R As Integer Do R=R+I I=I+1 Loop While I＜5 LblResult. Caption=Str$ (R) End Sub
在窗体上画一个命令按钮，然后编写如下程序： Sub S1(By Val x As Integer, By Val y As Integer) Dim t As Integer t=x x=y y=r End Sub Private Sub Command1_Click() Dim a As Integer, b As Integer a=10 b=30 S1 a，b Print"a=";"b=";b End Sub 程序运行后，单击命令按钮,．输出结果是______。A．a=30 b=10B．a=30 b=30C．a=10 b=30D．a=10 b=10
【程序说明】 计算下列算式的值。a，Ai为正整数，从键盘输入。其小∑Ai＝1+2…+ Ai，Ai!＝1 *2*3*Ai(i＝1，2… a)。【程序】SET TAIK OFFCLEARINPUT“M＝”TO MSTORE 0 TO S1，S2FOR I=1 TO M(8)DO SUB1DO SUB2ENDFOR? ” 所求算式的值为：“+ALLTRIM(STR(S1/S2，15，3))SET TALK ONPROCEDURE SUB1(9)FOR R＝1 TO AK＝K+RENDFOR(10)RETURNPROCEDURE SUB2(11)FOR P＝1 TO AT=T*PENDFOR(12)RETURN(8)A．INPUT“A＝”TO AB．INPUT“I=”TO IC．INPUT“R=”TO STR(R)D．INPUT“K＝”TOK
以下程序用来输出20个在开区间(10，87)上的随机整数R，每行输出4个整数。请完成空白处。Private Sub Command1 Click()For I=1 To 10R=Int(Rnd*76+11)Print R；If【 】Then PrintNext IEnd Sub
编写如下事件过程： Private sub sub1 (ByVal x1 As String, y1 As String) Dim xt As String Dim i As Integer i = Len(x1) Do While i＞= 1 xt = xt + Mid(x1, i, 1) i=i-1 Loop y1 = xt End Sub Private Sub Form. Click() Dim s1 As String, s2 As String s1= "teacher" sub1 s1, s2 Print s2 End Sub 程序运行后，单击窗体，则窗体上显示的内容是A．rehcaetB．tahreeeC．themeeD．eerthea
写出程序运行的结果Public class BasePublic virtual string Hello() {return “Base”;}Public class Sub:BasePublic override string Hello() {return “Sub”;}1. Base b = new Base(); b.Hello;2. Sub s = new Sub(); s.Hello;3. Base b = new Sub (); b.Hello;4. Sub s = new Base(); s.Hello;
在窗体中添加一个名称为Commandl的命令按钮，然后编写如下程序： Public x As Integer Private Sub Commandl_click() x＝10 Call s 1 Call s 2 MsgBOx x End Sub Pfivate Sub s1() x＝x+20 End Sub Private SubA．10B．30C．40D．50
当执行以下过程时，在名为1blResult的标签框内将显示______。 Private Sub cmdlt_ click() Dim I，R R=0 For I=1 To 5 Step 1 R=R+I Next i 1blResult．Caption=Str＄(R) End SubA． 字符串15B．整数15C．字符串5D．整数5
在窗体中添加一个名称为Command1的命令按钮，然后编写如下程序： Public x As Integer Private Sub Command1_Click() x=10 Call s1 Call s2 MsgBox x End Sub Private Sub sl() x=x+20 End Sub Private Sub s2() Dim x As Integer x=x+20 End Sub 窗体打开运行后，单击命令按钮，则消息框的输出结果为( )。A．10B．30C．40D．50
Operator needs to remove all leading comments from shell.script file. Which of the following vi sub－command can achieve this?() A. :r/^#//gB. :1,$ s/^#//gC. :sed s/^#//gD. :sub s/^#//g
Operator needs to remove all leading comments # from shell.script file. Which of the following vi sub-command can achieve this?（）A、:r/^#//gB、:1,$ s/^#//gC、:sed s/^#//gD、:sub s/^#//g
单选题假设X与y之间的相关系数为r1，y与x之间的相关系数为r2，则r1和r2之间的关系为（）Arsub1/sub＞rsub2/subBrsub1/sub＝rsub2/subCrsub1/sub＜rsub2/subD二者无关
单选题Operator needs to remove all leading comments # from shell.script file. Which of the following vi sub-command can achieve this?（）A:r/^#//gB:1,$ s/^#//gC:sed s/^#//gD:sub s/^#//g
单选题已知某线声源长度为l0，在线声源垂直平分线上距线声源r0和r的分别为Lp(r0)和Lp(r)，根据《环境影响评价技术导则声环境》，按公式Lp(r)=Lp(r0)-15lg(r/r0)近似计算该线声源的噪声影响时，应满足的条件是()。AprIsub0/sub且rsub0/subIsub0/sub /pBprIsub0/sub/3且rsub0/subIsub0/sub/3 /pCpIsub0/sub/3rspanI/spansub0/sub且Isub0/sub/3rsub0/subr0Isub0/sub /r0/pDp无条件限制 /p