《煤矿安全规程》对井下空气中二氧化氮的浓度是如何规定的？

下列工具中为需求分析常用工具的是( )。

A．PAD

B．PFD

C．N-S

D．DFD

An old man who lived in a small back street of my hometown had to tolerate（忍受） the nuisance（讨厌的人或事） of boys playing football and making a lot of noise outside his house at night.

One evening when the boys were particularly_21__，he went out to talk to them. He explained that he had just retired(退休) and was_22__when he could see or hear boys playing his_23_game，football. He would_24_ give them ￥25 each week to play in the street at night. The boys got_25_，for they could hardly believe_26_they were being paid to do something they__27_.

The first two weeks had passed，the boys came to the old man’s house，and went away__28__with their 25 Yuan. The third week when they came back，__29__，the old man said he hadn’t had much money__30__himself and sent them away with only 15 Yuan. The fourth week，the man said he had not yet 31  his paycheck from the government and gave them only 10 Yuan. The boys were very disappointed，but there was__32__much that they could do about it.

At the__33_of the fifth week，the boys came back and__34_at the old man’s door，waiting for their_35_.Slowly，the door opened and the old man appeared. He_36_that he could not afford to pay them 25 yuan_37_he had promised，but said he would give them  38 yuan each week without fail.

This was really too much for the boys. “You expect us to play seven days a week for only five yuan！” they yelled.“__39__！”

They stormed away and  40   played on the street again.

小题1: 

A．hot

B．noisy

C．troublesome

D．naughty小题2: 

A．happiest

B．excited

C．encouraged

D．bored小题3: 

A．interesting

B．amusing

C．acceptable

D．favorite小题4: 

A．more ever

B．therefore

C．willingly

D．forever小题5: 

A．shouted

B．cried

C．excited

D．smiled小题6: 

A．how

B．when

C．that

D．what小题7: 

A．expected

B．enjoyed

C．admired

D．respected小题8: 

A．happily

B．thankfully

C．gratefully

D．tearfully小题9: 

A．but

B．in addition

C．however

D．besides小题10: 

A．earned

B．saved

C．remained

D．left小题11: 

A．received

B．accepted

C．paid

D．given小题12: 

A．not

B．no

C．so

D．very小题13: 

A．final

B．end

C．start

D．beginning小题14: 

A．kicked

B．hit

C．beat

D．knocked小题15: 

A．rewards

B．awards

C．checks

D．wages小题16: 

A．expressed

B．apologized

C．stated

D．expected小题17: 

A．as

B．like

C．when

D．though小题18: 

A．5

B．10

C．15

D．20小题19: 

A．No way

B．No possible

C．No problem

D．No play小题20: 

A．ever

B．never

C．still

D．keep

预应力碳素钢丝的镦头最好采用热镦，这样钢丝镦头不易脆断( )

按照宪法修改程序的不同，可将宪法分为( )。

A．社会主义宪法和资本主义宪法
B．成文宪法和不成文宪法
C．刚性宪法和柔性宪法
D．钦定宪法、民定宪法和协定宪法

梯子的底宽不得小于（）CM。

A、30

B、40

C、50