making random picture boxes go on the form

[samqweqwe3]

hi
i am making a game in visual basic and when the picture box that you have to shoot resets, sometimes it resets off the form i use this code to make the picture box move randomly :

PbxMet.Top = Int(Rnd() * (Me.Height - PbxMet.Height))

key :
pbxmet = picture box you have to shoot
me = the form

anyone know how to keep it on the form

thanks in advance