I spend 20 dollars________this pair of sports shoes．

      A．buy           B．bought       C．to buy       D．buying

I spend 20 minutes ________ up for the bus every day．

1. A.
   in queuing
2. B.
   queueing
3. C.
   to queue
4. D.
   to queueing

Mary picked up a pencil and a piece of paper，saying，“Now，you want to earn money for the autumn camping trip，right?” Tom，her brother，nodded．He wasn’t able to go last year because he hadn’t earned enough money during the summer．This year he came up with a plan．
He made a necklace for his mother that everyone admired．They were surprised to learn that Tom had made it for her．Why not make more necklaces and sell them?
“OK，” said Mary，“The first thing you need to do is to figure out（计算）how much you have now．’’
“I have $20.00 in the bank，and $7.25 in my room，” explained Tom．
“That gives you a total of $27.25，” said Mary，“That is called your capital．The next thing you need to know is how much it will cost you to make each necklace．”
“Well，the pet shop will give me all the feathers the birds lose．I'll have to buy the beads（小珠子）and string，” said Tom．
Mary wrote on the piece of paper：
CAPITAL      $27.25
EXPENSES     Feathers                       no cost
String for 10 necklaces        $  2.50
Beads for 10 necklaces   +    $ 15.00
Total                        $ 17.50
“How much do you think you can sell such a necklace for?” asked Mary．
“Hmm，” Tom looked thoughtful and said，“There's a shop in town that sells almost the same kind of necklace for $ 7.50．If I charge（要价）$ 6.00，people will think that's a bargain．”
“OK．If you sell each necklace for $ 6.00，you'll make a good profit（利润）on each then，” said Mary．
“Hurray!” Tom cried，“If I sell 20 necklaces，I'll have enough from the profit for the camping trip and $10.00 left over．”
【小题1】The underlined word "bargain" in this story means “________”．