For my phone plan I can only send text messages to phone numbers who have Alltel or Verizon as their carrier. Is there a way to tell from the number if the person has one of the two?
How can you accurately measure 1 gallon of water if all you have is 3 gallon bucket and a 5 gallon bucket? All you are allowed to do is fill/empty the buckets or pour water from one to the other. You cannot collect spillage.