Private Sub Command1_Click()
r = Val(InputBox("人口年增长率为百分之几？"))
n = Int(Log(2) / Log(1 + r / 100) + 0.99999)
MsgBox ("13亿人口以年增长" & r & "%的增长率，" & n & "年后达到(超过)26亿")
End Sub
