Metro PCS was a service provider that was knows as a flat rate carrier for subscribers roaming in a limited area. Now it has introduced Travel Talk, an add-on to its plans that allows subscribers to roam in any US metro area. If the subscriber travels to another Metro PCS city, there is no additional charge for the calls; otherwise, calls cost between 49 and 79 cents per minute. MetroPCS has a limited service and hence this reflects on their other services provided to their customers....