General Motors said yesterday it has reached a preliminary agreement for selling its Hummer, the big sport utility vehicles and pickups it was persuaded to build by Arnold Schwarzenegger. GM has marketed Hummers as being made in the same factory as the Humvees that carry American soldiers into battle. Today, it's reported that the new owner will be a machinery company in China, the Sichuan Tengzhong Heavy Industry Machinery Company. Alex Taylor is senior editor at Fortune magazine.