【简答题】无水无氧操作有哪几种具体技术?相比各有什么特点?
【简答题】一手动蜗杆传动起重装置如图4-6所示。已知该蜗杆传动的有关参数为:m=8mm,q=8,z 1 =1,z 2 =40;卷简直经D=200mm。试求: (1) 使重物上升1m手柄所转圈数n 1 ,并在图中标出手柄的转向; (2) 若蜗杆和蜗轮之间当量摩擦系数f v =0.2,求传动的啮合效率η 1 ,并说明该传动能否自锁? (3) 若起重量Q=10 4 N,人手推力P=200N,求手柄长度L; (4)...
【单选题】What is the woman going to do this Sunday afternoon?
A.
She is going to an exhibition abroad.
B.
She is going to a wedding ceremony.
C.
She is going on a voyage over the Pacific.
D.
She is going to an art museum.
【单选题】“最古之史,实为方志”是 ______ 提出的。
【单选题】“最古之史,实为方志”是____提出的。(出题单位:重庆市委直属机关工委 推荐单位:重庆学习平台)
【简答题】This is a picture of Mr Wang’s family. The man in the middle is Mr Wang, the father. The woman is the mother. They have two daughters. One is Wang Fang. She is twelve. The other is Wang Li. She is thi...
【单选题】What is the woman trying to accomplish in this conversation?
A.
Convince the man that they should rest for a while.
B.
Teach the man about the types of clouds.
C.
Entertain the main with some interesting weather stories.
D.
Persuade the man to turn around and go down the hill.
【单选题】Man: Is the freeway always this deserted? Woman: It's the middle of the day. Everyone is at work. Question: What does the woman imply?
A.
The freeway isn't usually as empty as it is now.
B.
Many prefer to eat dessert in the middle of the day.
C.
The freeway isn't working in the middle of the day.
D.
Most people prefer to work at night.
【简答题】他生于群雄并起的炎汉季世,待到刘皇叔三顾频繁之际,曹阿瞒早已横扫诸袁,奄有了北方的大步,碧眼儿也坐稳了江东,人们常常扼腕叹息,叹息他虽逢明主却未获天时,然而,即便这样,他还是竭尽人谋,提出定荆州、定西川、三分天下而后联吴伐魏的正确战略。殊不料,彝陵一败,先主崩殂,在极度的艰难困苦之中,他毅然挑起军国重担,坚持北伐,直到赍志以殁。 北伐中原利耶弊耶?那是研究者们的事情。历史最怕的是假设。可是,有一些...