下列说法中正确的是( ) A.小明推一辆汽车没推动,是因为他的推力小于车受到的摩

题型:选择题

问题:

下列说法中正确的是(  )

A.小明推一辆汽车没推动,是因为他的推力小于车受到的摩擦力

B.在空中下落的排球,运动得越来越快,是因为排球具有惯性

C.地球同步卫星相对地球静止,是因为受到平衡力的作用

D.小安站在磅秤上,小安对磅秤的压力和磅秤对小安的支持力大小一定相等

考点:惯性现象力与运动的关系力作用的相互性
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阅读表达。

     The new school term is coming. Now the school clerks are planning a new timetable for Class 7 ,

Grade 9.    

     There are six classes every day, four in the morning and two in the afternoon. The students have a

math class every day. And they have seven English classes in a week. Two of them are given by a foreign

teacher and should be arranged together on Thursday morning.    

     There are five Chinese classes in a week. Two of them should also be arranged one after the other

for the students to write their corupositions.      

     They have two physics classes in a week but on different days. Besides these, there is an art class

every Wednesday afternoon.      

     It's necessary and important for students to take enough exercise. So they have two PE elsses every

week. And they can do outdoor activities after school every afternoon.

阅读短文,完成表格。

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小可同学在学习了近一年的初中化学后,总结了一些说法,判断这些说法是否正确.若正确,在右边空白栏打“√”;若错误,用溶质的化学式或反应的化学方程式证明.

说        法溶质的化学式或反应的化学方程式
不是所有的溶液都是无色的______
只有碱溶液才显碱性______
有盐和水生成的反应一定是中和反应______
所有复分解反应只能生成一种沉淀______

题型:选择题

电流速断保护

题型:选择题

抗结核药物中INH的成人常规每日用量是(  )

A.50 mg

B.100 mg

C.150 mg

D.200 mg

E.300 mg

题型:选择题

小儿3岁,低热咳嗽4天,呼吸平稳,双肺散在干湿啰音,可能诊断为()

A.急性支气管炎

B.支气管肺炎

C.毛细支气管炎

D.金黄色葡萄球菌肺炎

E.衣原体肺炎

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