水平地面上有一块重量是2N的静止石块,一个小孩用10N的力踢石块,使石块滑行了1

题型:选择题

问题:

水平地面上有一块重量是2N的静止石块,一个小孩用10N的力踢石块,使石块滑行了1M的距离,则小孩对石块所做的功是[    ]

A.10J

B.2J

C.12J

D.条件不足,无法确定

考点:
题型:选择题

People in the USA say "_______" while people in Britain say "autumn".[ ]

A. lift              

B. vacation          

C. fall            

D. soccer

题型:选择题

According to a recent survey, marriage is fattening. Cited as evidence is the survey’s finding that the average woman gains 23 pounds and the average man gains 18 pounds during 13 years of marriage.
The answer to which of the following questions would be most relevant in evaluating the reasoning presented in the survey

A.Why was the period of time studied in the survey 13 years, rather than 12 or 14

B.Did some of the men surveyed gain less than 18 pounds during the time they were married

C.How much weight is gained or lost in 13 years by single people of comparable age to those surveyed

D.Were the women surveyed as active as the men surveyed, at the time the survey was made

E.(E) Will the reported gains be maintained over the lifetimes of the persons surveyed

题型:选择题

垄断竞争厂商的长期均衡与短期均衡的惟一区别是长期均衡多一个条件,即()。

A.AR=AC

B.厂商的主观需求曲线必须和长期平均成本曲线相切

C.P=AC

D.主观需求曲线与实际需求曲线相交

题型:选择题

物资在保管期间,都要求有一个()的温湿度。

题型:选择题

治疗短暂性脑缺血发作气虚血瘀脉络瘀阻证,应首选( )

A.镇肝熄风汤
B.补阳还五汤
C.黄连温胆汤合桃红四物汤
D.羚角钩藤汤
E.半夏白术天麻汤

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