【单选题】The Hydrogen Economy It seems like every day there is a new announcement in the news about automobiles powered by fuel cells. The promises are great, since fuel ceils have the potential to very quickl...
【简答题】Electronic commerce, commonly known as 1 , is the buying and selling of 2 or services over electronic 3 such as the Internet and other computer networks. From the point of view of 4 , e-commerce may m...