阅读理解

    This happened about one thousand and seven hundred years ago．One day somebody sent Cao Cao, the king of Wei an elephant．Cao Cao wanted to know its weight(重量)．“Who can think of a way to weigh it?”he asked．But nobody knew what to do because there was nothing big enough to weigh it．

    Then Cao Chong, one of the king's young sons, came up and said, “Father, I've got an idea．Let me have a big boat and a lot of heavy stones, and l'll be able to find out the weight of the elephant．''

    Cao Cao was surprised, but he told his men to do as the boy asked．When the boat was ready, the boy told a man to lead the elephant down into it．The elephant was very heavy, and the water came up very high along the boat's side．Cao Chong made a mark along the water line．

    After that the man drove the elephant onto the bank．Cao Chong then told the men to put heavy stones into the boat until the water again came up to the line．

    Cao Chong then told the men to take the stones off the boat and weigh them one by one．He wrote down the weight of each stone and then added up all the weights．In this way he got the weight of the elephant．