下列说法错误的有( )①所有的实数都有平方根②所有的实数都有算术平方根③所有的实

题型:选择题

问题:

下列说法错误的有(  )
①所有的实数都有平方根  ②所有的实数都有算术平方根  ③所有的实数都有立方根  ④所有的实数都有绝对值  ⑤所有的实数都有倒数.
A.1个B.2个C.3个D.4个
考点:实数的定义
题型:选择题

如图,一块质量为M=2kg,长L=1m的匀质木板放在足够长的光滑水平桌面上,初始时速度为零.板的最左端放置一个质量m=1kg的小物块,小物块与木板间的动摩擦因数为μ=0.2,小物块上连接一根足够长的水平轻质细绳,细绳跨过位于桌面边缘的定滑轮(细绳与滑轮间的摩擦不计,木板与滑轮之间距离足够长,g=10m/s2).

(1)若木板被固定,某人以恒力F=4N向下拉绳,则小木块滑离木板所需要的时间是多少?

(2)若木板不固定,某人仍以恒力F=4N向下拉绳,则小木块滑离木板所需要的时间是多少?

(3)若人以恒定速度v1=1m/s向下匀速拉绳,同时给木板一个v2=0.5m/s水平向左的初速度,则木块滑离木板所用的时间又是多少?

题型:选择题

患者章某,大热烦渴,口燥咽干,错语不眠,吐血衄血,舌红苔黄,脉数有力。治宜选用()。

A.犀角地黄汤

B.凉膈散

C.竹叶石膏汤

D.黄连解毒汤

E.普济消毒饮

题型:选择题

患者男性,58岁。患有慢性支气管炎并阻塞性肺气肿。近日因感冒咳喘加重,并有低热。就诊前2小时突然喘息加剧,出大汗,用解痉止喘药均不能缓解。体检:喘憋状态,口唇发绀,左肺叩诊过清音,右肺鼓音,右肺呼吸音消失,左侧呼吸音增粗并有少量干啰音。

经急救后病情有所缓解,缓解的体征之一是()

A.右侧胸廓饱满

B.右肺叩诊鼓音

C.右肺呼吸音逐渐恢复

D.左肺叩诊鼓音

E.左侧胸廓饱满

题型:选择题

胆汁中与脂肪消化、吸收有关的主要成分是

A.胆盐

B.胆固醇

C.卵磷脂

D.胆色素

题型:选择题

Letter A
Dear Rose,
I like your programmes very much. I’m now writing to ask you something about American social customs. My American friends want me to join them in their dinner party. I am very happy and have decided to go, but I’m a little worried about it, too. The social customs in my country are very different from here, so I’m afraid of making mistakes.
Should I bring a present, such as sweets or flowers Should I arrive on time or a little late At the dinner table, how can I know which fork or knife to use How can I let the family know that I’m thankful for their kindness
Wang Lin
Letter B
Dear Wang Lin,
It’s a good idea to bring a small present when you go to a dinner party. Flowers are always nice, or you may bring a bottle of wine if you know that your friends drink it.
You should arrive on time or five to ten minutes late. Don’t get there early. If you’re going to be more than fifteen minutes late, you should call and tell them.
Try. to be free at the dinner table. If you don’t know about choosing the right fork or knife, just watch the other people, and follow them. If you still have no idea of what to do, ask the person next to you.
If you like the food, say so. Of course, you’ll thank them for the meal and for their kindness. It’s also a good idea to send a thank you card the day after.
Rose

Which of the following is NOT proper for joining in a dinner party

A. Get there 15 minutes earlier.
B. Make yourself at home.
C. Follow others to use forks and knives.
D. Thank your friends for the meal.

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