There I'm afraid I can't help you. Log on to the web site of your phone service provider and from there you should be able to find a price table. My guess is that as you can already connect to a 3G network your only additional cost will be if you want to exceed your current download limit, whatever that is.
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Do you know that we're all in line for succession to the throne? Really?
Well, if forty-eight million, two hundred thousand, seven hundred and one people died I'd be Queen.