实现该功能的VB程序段如下：

Function space(x As Integer)As String        ‘输出格式化，设置左侧的空格数量

  Dim n As Integer

  For n=9 To x Step-1

     ①  

  Next n

End Function

Private Sub Form_Load()

  Dim t As Long，i As Integer，n As String

  Dim a(1 To 9)As String

  Dim b(1 To 9)As String

  Const num=“987654321”

  For i=1 To 9

    t=t*10+i

    a(i)=space(i)+CStr(t)  ‘CStr函数的功能是将数值转为字符，转换时不会添加空格

       ②   

    n=n+a(i)+“*8+”+CStr(i)+“=”+b(i)+Chr(13)       ‘Chr(13)实现换行处理

  Next i

  Label1．Caption=n

End Sub

请根据算法将下列程序补充完整。

Function prime(a As Integer)As Boolean

  Dim j As Integer

  prime=True

  j=2

  Do While prime And j<=a\2

   If a Mod j=0 Then

     prime=False

     Exit Do

   End If

{#blank#}1{#/blank#}

    Loop

End Function

Private Sub Command1_Click( )

  Dim i As Integer, a As Integer, b As Integer

  Dim count As Integer

  a=Val(Text1.Text)

  b=Val(Text2.Text)

  For i=a To b

    If{#blank#}2{#/blank#}=True Then

       List1.AddItem Str(i)

       count=count + 1

     End If

  Next i

   Label1.Caption=“素数共有” + Str(count) + “个!”

End Sub

请回答下列问题：