GlobalFon is an international communication company, which offers international prepaid calling cards. They introduced three different types of cards, (1) AsiaFon: is cheapest for calling all over Asia. (2) EuroFon: offers economical rates for all over Europe and UK. AmericanoFon: offers very attractive rates for USA and Canada. Every card has attributes for activation (True/False), activation date, time remaining, and no. of call made. The card is available in domination of $5, $10 and $20. Assuming there are serial numbers on card for keep track of production system, and a 14-digit code for activating the card. The validity for card after activation is 45 days. AsiaFon; offers 25cent per minutes. EuroFon charges 16 cents per min. AmercanoFon charges 12 cents per min. The billing least count is min. The company wants object oriented software to handle the service of international calling. You are only required to developed classes for processing cards with basic functionality.