在窗体中添加一个命令按钮(名为Command1)和一个文本框(名为text1),编写如下事件过程: Private Sub Command1_Click() Dim x As Integer,y As Integer,z As Integer x=3:y=5:z=10 Me!Text1="" Call f(x,y,z) Me!text1=z End Sub Sub f(a As Integer,b As Integer,c As Integer) c=b*a End Sub 打开窗体运行后,单击命令按钮,文本框中显示的内容是______。