关于二力平衡,下列说法正确的是:[ ] A、作用点相同,大小相等,方向相反的二个

题型:选择题

问题:

关于二力平衡,下列说法正确的是:[ ]

A、作用点相同,大小相等,方向相反的二个力一定是一对平衡力。

B、一个物体在两个力作用下,如果保持匀速直线运动状态,那么这二力肯定是二力平衡的。

C、放在水平桌面上的墨水瓶对桌面的压力与桌面对它的支持力是一对平衡力。

D、作用在一个物体上的两个力,如果在同一直线上,大小相等,方向相反,那么这两个力一定是平衡的。

考点:二力平衡的定义及条件
题型:选择题

男,55岁,上腹部无规律性疼痛、消瘦一年入院,胃镜示胃小弯处有一个2cm×2cm大小溃疡,边缘不整齐,有坏死,少量渗血。查体表淋巴结对诊断意义最大的是()

A.颈前、颈后

B.锁骨上窝

C.枕后

D.腋下

E.腹股沟

题型:选择题
1
7
+b×
1
7
=30,那么2(a+b)=______.
题型:选择题

Read the argument and the instructions that follow it, and then make any notes that will help you plan your response. Write your response on a separate sheet of paper. If possible, type your essay on a word processor.
The following statement appeared in a consumer magazine:
A fear of crime has led many homeowners to purchase monitored burglar alarm systems, but these people are wasting their money. The primary benefit of any burglar alarm system is one of deterrence, and this effect can be achieved just as well by having a sign in front of the house suggesting that the house is equipped with an alarm, whether or not the alarm system is monitored or even exists. Moreover, if a sign fails to deter burglars from entering a house, there is very little chance that the guards who monitor the alarm system will arrive at the home in time to catch the burglars, since the burglars will surely leave as soon as the alarm sounds. Therefore, while it makes sense to have a sign suggesting that a house has a monitored alarm, and it may make sense to have an audible alarm, there is no reason to pay the high monthly fee for a monitored system.
Discuss how well reasoned you find this argument. In your discussion, be sure to analyze the line of reasoning and the use of evidence in the argument. For example, you may need to consider what questionable assumptions underlie the thinking and what alternative examples or counterexamples might weaken the conclusion. You can also discuss what sort of evidence would strengthen or refute the argument, what changes in the argument would make it more logically sound, and what, if anything, would help you better evaluate its conclusion.

题型:选择题

以治肺胃损伤之咯血、吐血最宜的是

A.大蓟
B.地榆
C.三七
D.白及
E.蒲黄

题型:选择题

急性心肌梗死3天后的患者()

A.加强锻炼,提高耐力

B.绝对卧床休息,限制探视

C.可照常活动,仅避免重体力活动

D.适当床边活动

E.出院恢复工作

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