Shipping confusion

[hdavy2002]

I read this http://www.prestashop.com/wiki/Shipping/

My confusion is:

I sell multiple items from diffrent manufactureres.

Eg: Manufacturer A
Manufacturer B
Manufacturer C


Now

Manufacturer A charges 8$ flat rate to US and 15 % international (worldwide)

Manufacturer B charges 12$ flat rate to US and 45 % international (worldwide)

Manufacturer C charges 5$ flat rate to US and 17 % international (worldwide)

With the above link, creating shipping charges for Manufacturer A will work perfectly, my confusion is what happens when a user selects a product from Manufacturer C, his shipping rates would be different,. I am confused at this point.

Thanks all