The matrix A is[img=44x19]1803b6ad8347a80.png[/img]. If the eqaution Ax=0 has only the trivial solution , thenA is invertible.

If3a=8band15b=4c,thena/c=______. A: 4/5 B: 8/15 C: 32/45 D: 15/18 E: 11/9

Complete the dialogues with the words and expressions given in the box.find out if Mr. Smith could see me what can I do for you he is free thenA: Good morning. Is Mr. Smith in?B: No, I’m afraid not. But _____________ ? I’m Mrs. Smith.A: I’m calling to _______________at 3 tomorrow afternoon? I have some problems to discuss with him.B: Yes, __________________ . I’ll tell him you’ll be coming.

在窗体上画一个命令按钮(其Name属性为Commandl)，然后编写如下代码： Private Sub Commandl_Click() Dima(5) Fori=0 To 4 A(i)=i+1 t=i+1 If t=3 Then Print a(i) A(t-1)=a(i-2) Else A(t)=a(i) End If Ifi=3 Thena(i+1)=a(t-4) A(4)=1 Printa(i) NextI End Sub 程序运行后，单击命令按钮，输出结果是上______。