放在水平地面上重500N的木箱,受到水平向右100N推力时,恰好作匀速直线运动,

题型:填空题

问题:

放在水平地面上重500N的木箱,受到水平向右100N推力时,恰好作匀速直线运动,木箱受到的摩擦力是______;在木箱下垫上几根圆木后仍然匀速水平向右推,此时木箱受到的摩擦力______(填“增大”、“减小”或“不变”).

考点:二力平衡的定义及条件
题型:填空题

A man came back home from work late, tired, to find his six-year-old son waiting for him at the door.

“Daddy, how much money do you make an hour?”

“If you want to know, I make $20 an hour.”

“Oh,” the little boy replied, with his head down. He thought for a moment, looked up and said, “Daddy, could you lend me $10?”

The father was furious, “If you asked for money to buy a toy or some other rubbish, then go straight to your room and think why you are being so selfish!”

The little boy quietly went to his room and shut the door. After about an hour or so, the father calmed down, and started to think, “Maybe he really needs to buy something and he didn’t ask for money very often.” So he went to the little boy’s room.

“Sorry! Maybe I was too hard on you just now,” said the man. “Here’s $10.”

“Oh, thank you, Daddy!” the boy said gladly. Then, the boy took out some coins. When the father found that the boy already had some money, he got angry again.

“Why do you want more money since you already have some?” the father shouted angrily.

“Because I didn’t have enough, but now I do,” the little boy replied, “Daddy, I have $20 now. Can I buy an hour of your time? Please come home early tomorrow. I would like to have dinner with you.”

小题1:How much does the man make if he works 10 hours?

A.$20.

B.$50.

C.$100.

D.$200.小题2:In this passage, the underlined word “furious” means ___________.

A.very angry

B.quite happy

C.too excited

D.a little tired小题3:The boy wanted to buy ___________ with twenty dollars.

A.a new book for himself

B.a nice present for his father

C.a toy for his own birthday

D.an hour of his father’s time小题4:From this passage, we can infer (推断) that the boy’s father __________.

A.often played with his son

B.spent little time with his son

C.didn’t love his son at all

D.often came back home early

题型:填空题

有关3/4冠牙体预备的正确叙述是()。

A.临床牙冠长,倒凹大者,邻面冠边缘应止于龈缘

B.上前牙切斜面由舌侧斜向唇侧

C.在切端斜面舌1/3处,做一顶角90°的沟

D.舌轴壁的倒凹不必消除,可以舌隆突为界分两段预备

E.邻沟与邻面的线角清晰,有棱角

题型:填空题

气血精津液的相互化生,属于气的

A.推动作用

B.防御作用

C.固摄作用

D.气化作用

题型:填空题

EDI以确定的报文格式形式进行数据传输和信息交换。 ( )

题型:填空题

极易泛油的药材组是

A.扁豆花、佛手片
B.天冬、郁李仁
C.乳香、没药
D.桔梗、百部
E.玫瑰花、冰片

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