Tom walked into a shop. It had a sign outside: " Second-hand clothes bought and sold. " He was carrying an old pair of trousers and asked the owner of the shop, " How much will you give me for these? " The owner looked at them and said " Two dollars. " " What? " Tom said, " I had guessed they were worth at least five dollars. " " No. " said the owner, " They weren't worth a cent more than two dollars." "Well," said Tom, taking two dollars out of his pocket. " Here is your money. These trousers were hanging outside your shop. The list price was six dollars and a half. But I thought that was too much money, so I wanted to find out how much they were really worth." Then he walked out of the shop with the pair of trousers and disappeared before the owner could think of anything to say. From the story we know that   _   cheaper than the list price.
the owner sold the trousers two dollars Tom sold the trousers one and a half dollars the owner bought the trousers three dollars Tom bought the trousers four dollars and a half