关于VB迭代法的用法，帮忙用VB写下代码。。

Private Sub Form_Click()
Form1.AutoRedraw = True
Cls
Dim P15 As Single, P20 As Single, A As Single, Tt As Single
Dim T As Single, P151 As Single, I As Integer
Dim E As Single
E = Exp(1)
T = Val(InputBox("t=", "输入", 1))
P20 = Val(InputBox("p20=", "输入", 30))
Tt = T
P15 = P20
Print "t="; T, "p20="; P20
I = 0
Do
I = I + 1
P151 = P15
A = 186.9696 / P15 ^ 2 + 0.4862 / P15
P15 = P20 / E ^ -A * Tt * (1 + 0.8 * A * Tt)
Print I, "p151="; P151, "p15="; P15
Loop While Abs(P15 - P151) >= 0.0005
Print "最后结果为：p15="; P15
End Sub