At two o’clock a bank robber stole in.“This is a holdup,” the man said loudly. He took a gun from under his jacket, pointing to George.“Hand it over!” George reached into his money-box and took all the bills from the top part-close to six thousand dollars. The robber took them and turned to leave.
Then, while everyone watched the robber, George calmly lifted the top part of the money-box, took bills from the bottom part and put them into his own pocket secretly.
The door was shut and the bank robber was gone. George fainted（晕倒）.
As soon as he was safely behind his bedroom door, George counted the money. He had eight thousand dollars. He was very happy.
The next morning, while the others were examining the bank's records, George was called into Mr Burrow's office and was introduced to Mr. Carruthers, who used to be president of the bank.
“Good morning, George, I was sorry to give you a hard time yesterday, but with all the banks being robbed these days I thought it would be a good idea to prove that our little bank can be robbed too. I have retired（退休）, but I’m always thinking of our bank. That's why I played my little game yesterday, just to keep everyone on his toes（趾）. Now, I have put the money back in your money-box all six thousand.”
小题1:This passage tells us ______.
A．a serious case
B．one part of a play
C．a humorous story
D．a meaningful story小题2: Which of the following do you think is true?
A．George wanted to protect the money for the bank.
B．George had been thinking of taking money away.
C．This bank had been robbed several times.
D．Nobody knew the bank would be robbed that day.小题3: Why was George called into Mr. Burrow’s office?
A．His stealing money was disclosed.
B．Mr. Burrow wanted to say sorry to him.
C．Mr. Carruthers wanted to explain the whole thing to him.
D．Mr. Burrow wanted to tell him the money had been put back.小题4: In this article “to keep everyone on his toes” means “______”.
A．to make everyone work hard
B．to keep everyone standing straight
C．to make everyone do a kind of exercise
D．to keep everyone paying attention to the coming danger小题5: Which sentence can be used to end the story?
A．George turned cold with fear.
B．George turned red with anger.
C．George was pleased with the end.
D．George was disappointed with the end.
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，第2s末位置为
。请分别求出第1s内和第2s内质点位移的大小和方向。