皮皮学，免费搜题
登录
logo - 刷刷题
搜题
【单选题】
可分为珍贵文物和一般文物的是
A.
可移动文物
B.
珍贵文物
C.
一般文物
D.
不可移动文物
手机使用
分享
复制链接
新浪微博
分享QQ
微信扫一扫
微信内点击右上角“…”即可分享
反馈
参考答案：
举一反三
【判断题】在计算蜗杆传动的啮合效率时,蜗杆和蜗轮齿面间的当量摩擦系数可根据两者的相对滑动速度选取
A.
正确
B.
错误
查看完整题目与答案
【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)...
查看完整题目与答案
【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.
查看完整题目与答案
【判断题】在计算蜗杆传动啮合效率时，蜗杆和蜗轮齿面间的当量摩擦系数可根据两者的相对滑动速度选取。
A.
正确
B.
错误
查看完整题目与答案
【单选题】“最古之史,实为方志”是 ______ 提出的。
A.
章学诚
B.
梁启超
C.
康有为
D.
毛泽东
查看完整题目与答案
【单选题】急性中毒患者,当诊断不明时,最应选择的洗胃液是
A.
1:15 000高锰酸钾
B.
温开水或生理盐水
C.
牛奶
D.
3%过氧化氢
E.
2%～4%碳酸氢钠
查看完整题目与答案
【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)
A.
章学诚
B.
梁启超
C.
康有为
D.
毛泽东
查看完整题目与答案
【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...
查看完整题目与答案
【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.
查看完整题目与答案
【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.
查看完整题目与答案
相关题目：
【判断题】在计算蜗杆传动的啮合效率时,蜗杆和蜗轮齿面间的当量摩擦系数可根据两者的相对滑动速度选取
A.
正确
B.
错误
查看完整题目与答案
【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)...
查看完整题目与答案
【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.
查看完整题目与答案
【判断题】在计算蜗杆传动啮合效率时，蜗杆和蜗轮齿面间的当量摩擦系数可根据两者的相对滑动速度选取。
A.
正确
B.
错误
查看完整题目与答案
【单选题】“最古之史,实为方志”是 ______ 提出的。
A.
章学诚
B.
梁启超
C.
康有为
D.
毛泽东
查看完整题目与答案
【单选题】急性中毒患者,当诊断不明时,最应选择的洗胃液是
A.
1:15 000高锰酸钾
B.
温开水或生理盐水
C.
牛奶
D.
3%过氧化氢
E.
2%～4%碳酸氢钠
查看完整题目与答案
【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)
A.
章学诚
B.
梁启超
C.
康有为
D.
毛泽东
查看完整题目与答案
【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...
查看完整题目与答案
【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.
查看完整题目与答案
【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.
查看完整题目与答案
参考解析：
知识点：
题目纠错 0
发布
创建自己的小题库 - 刷刷题