小吴为了研究冒泡排序过程中数据的“移动”情况，编写了一个VB程序，功能如下：在列表框list1中显示排序前数据（存储在数组a中），在文本框text1中输入初始位置（即下标值），单击“排序”按钮command1后，在标签label1中显示指定初始位置的数据在排序过程中的位置变化情况，排序后的数据显示在列表框list2中。程序运行界面如图所示。
实现上述功能的VB程序如下，但加框处代码有错，请改正。

Dim a(1 To 8) As Integer
Dim n As Integer
Private Sub Form_Load()

a(1) = 30: a(2) = 47: a(3) = 30: a(4) = 72

a(5) = 70: a(6) = 23: a(7) = 99: a(8) = 24

n = 8

For i = 1 To 8

List1.AddItem a(i)

Next i

End Sub
Private Sub Command1_Click()

Dim i As Integer, j As Integer, k As Integer

Dim pos As Integer

Dim s As String

s = Text1.Text

pos = Val(Text1.Text)

For i = 1 To n – 1

For j = n To i + 1 Step -1
If a(j) < a(j - 1) Then

   _____________

a(j - 1) = a(j)

a(j) = k
'如果pos位置的数据参与交换，则更新pos值，记录pos变化位置
If pos = j Then
pos = j - 1
s = s + "→" + Str(pos)
_________
pos = j
s = s + "→" + Str(pos)
End If
End If
Next j

Next i

Label1.Caption = "位置变化情况：" + s

For i = 1 To n

List2.AddItem Str(a(i))

Next i

End Sub

（加试题）以下 VB 程序段用插入排序的方法实现 10 个数据升序排序。
Dim tmp As Integer
Dim a(1 To 10) As Integer
Private Sub Form_Load
'随机生成 10 个不重复的数存入数组 a,代码略
End Sub
Private Sub Command1_Click
For i = 2 To 10
If a(i) < a(i- 1) Then tmp = a(i)
For j = ①     To 1 Step -1   '依次后移
If tmp > a(j) Then Exit For
②
Next j
③ '插入数据
End If
Next i End Sub 要实现上述功能，方框①②③中的语句分别是（   ）

A．i-1a(j+1)=a(j)a(j+1)=tmp

B．i-1a(j+1)=a(j)a(j)=tmp

C．10a(j)=a(j+1)a(j)=tmp

D．10a(j)=a(j+1)a(j+1)=tmp

小李编写一个统计学生选考科目的 VB 程序，算法的基本思想是：检查每位学生选课组合的编码是否有效，对有效选择结果进行科目统计，根据各科占有效人数的百分率求出各科排名｡程序运行时，单击“显示”按钮 Command1，学生选课数据显示在列表框 List1 中，各科编号及对应科目名称显示在列表框 List2 中，单击“统计”按钮 Command2，选课结果按各科百分率由高到低显示在列表框 List3 中，程序运行结果如图所示｡

现上述功能的 VB 程序如下，请回答下列问题：
（1）学生选课的编码数据存储在数据表中，其字段名为__________________｡
（2）请在划线处填入合适的代码｡
Dim ach(1 To 500) As String  '存储各学生选课编码
Dim bno(1 To 10) As Integer '存储各科目编号
Dim bname(1 To 10) As String '存储各科目名称
Dim bnum(1 To 10) As Integer  '存储各科目被选次数
Dim bmc(1 To 10) As Integer '存储各科目被选的名次
Dim n As Integer, num As Integer
Private Sub Command1_Click()
Dim i As Integer, km As String
km = "物理化学生物政治历史地理技术"
Dim cn As New ADODB. Connection, rs As New
ADODB. Recordset, sql As String
cn. Open "provider=Microsoft. Jet. oledb. 4. 0;Data Source =" + App. Path + " \students. mdb"
rs. Open "select ∗ from choose", cn
Do While Not rs. EOF
n = n + 1 : ach(n) = rs. Fields("subject") : rs. MoveNext
Loop
rs. Close: cn. Close
Set rs = Nothing
Set cn = Nothing
For i = 1 To 7
bno(i) = i: bname(i) = Mid(km, (i - 1) ∗2 + 1, 2)
List2. AddItem Str (bno (i)) + " - - -" +bname(i)
Next i
End Sub
Private Sub Command2_Click()
Dim i As Integer, j As Integer, k As Integer
Dim c As String, per As Integer
For i = 1 To n
If check(ach(i)) =True Then
For j = 1 To 3
c = Mid(ach(i), j, 1)
bnum(Val(c)) = ①_________
Next j
num = num + 1
End If
Next i
i = 1
Do While i <= 7  '该循环得到各学科被选人数的名次
bmc(i) = 1
For j = 1 To 7
If bnum(j) > bnum(i) Then ②__________
Next j
i = i + 1
Loop
For i = 1 To 7
For j = 1 To 7
If ③_________Then
per = Int(bnum(j) ∗ 100 / num ∗ 100)/ 100
List3. AddItem Str(bno(j)) + "---" +bname(j) + "---" + Str(per) + "%"
End If
Next j
Next i
End Sub
Function check(s As String) As Boolean
'代码略，若学生选科代码有效，函数返回 True，否则返回 False
End Function

某排序算法，其VB代码如下：
i = 1
Do While i<= 5
If i = 0 Or a(i - 1) <= a(i) Then
i = i + 1
Else
t = a(i): a(i) = a(i - 1): a(i - 1) = t
i = i - 1
End If
Loop
数组元素a(0)到a(5)依次为：“0，61，22，43，89，27”，经过该程序段处理后，数组元素a(4)的值为（ ）

A．43

B．89

C．61

D．27

   小杰为学校教务处编写了一个排考场座位的VB程序，考场采用“6排5列”共30人的模式，程序执行后，考生的考号与姓名显示在列表框List1中，单击“考场座位”按钮，考场号与座位显示在Text1中，程序运行界面如图所示，数据表如图

 
实现上述功能的VB程序如下，请回答下列问题：
（1）程序中读取的数据库文件是____________
（2）当“Form_load() 事件处理过程运行结束后，变量x的值为___________
（3）请在划线处填入合适的代码
Dim sName(100) As String
Dim kh(100) as string
Private Sub Command1_Click()
Dim y As Integer
Dim start As Integer　 　 '考场第1位数据元素的下标
Dim pa As Integer '数据库导入VB时学生数据下标
Dim pb As Integer '考场座位数据下标
Dim i As Integer，j As Integer，k As Integer，m As Integer
Dim kcsName(100) As String
start = 1
pa = start
recCount = x-1
If recCount Mod 30 <> 0 Then
_______________
For i = 1 To y　　　 '将当前考生人数添加到30的整数倍　　　　
recCount = recCount +1
sName(recCount) = " "
Next i
End If
For j = 1 To recCount / 30 　　
pa = start 　　
pb = start 　　
For i = 1 To 30
kcsName(pb) = sName(pa)
pb = pb +1
If  i Mod 5 = 0 Then
pa = start +i \5
Else 　
________________
End If 　　
Next i 　　
start = start +30
Next j
Text1.Text = " "
start = 1
For k = 1 To recCount /30 　　
m = start 　　
Text1.Text = Text1.Text + "第" + Str(k) + "考场" + vbCrLf 　　
'vbCrLf为换行标志符，实现Text1中内容换行显示　　
For i = 1 To 6
For j = 1 To 5
Text1.Text = Text1.Text +"　 " +kcsName(m)
m = m +1
Next j
Text1.Text = Text1.Text +vbCrLf 　　
Next i 　　
Text1.Text = Text1.Text +vbCrLf +vbCrLf
______________________
Next k
End Sub
Private Sub form_load()
Dim conn As New ADODB.Connection
Dim rs As New ADODB.Recordset
conn.ConnectionString = "provider=microsoft.ace.oledb.12.0;data source=" & App.Path & "/kaochang.accdb"
conn.Open
Set rs.ActiveConnection = conn
rs.Open "select * from banji"
x = 1
List1.AddItem "　考号　　姓名"
Do While Not rs.EOF    '
kh(x) = rs.fields("kh")
sName(x) = rs.fields("xm")
List1.AddItem kh(x) + "  " + sName(x)
x = x + 1
rs.MoveNext
Loop
rs.Close
End Sub