Hello again.
Your Syntax is wrong again. You have nested functions for your radio buttons inside the submit button function. This make is so your variable "radioButtonPressed" is never triggered. I am assuming that all the elements on your stage are properly named. I added a trace statement so you can see what Flash thinks radioButtonPressed should be. Your code should look like this:

btnSubmit.onPress = function()
{
trace(radioButtonPressed);
if (radioButtonPressed == 1)
{
Yes_cover_mc._visible = false;
}
if (radioButtonPressed == 2)
{
No_cover_mc._visible = false;
}
if (radioButtonPressed == 3)
{
No_cover_mc._visible = false;
}
if (radioButtonPressed == 4)
{
No_cover_mc._visible = false;
}
};

cbSpain.onPress = function()
{
radioButtonPressed = 1;
};
cbNorway.onPress = function()
{
radioButtonPressed = 2;
};
cbMacedonia.onPress = function()
{
radioButtonPressed = 3;
};
cbItaly.onPress = function()
{
radioButtonPressed = 4;
};