(1)关于近代物理,下列说法正确的是________。(填选项前的字母) A.射

题型:选择题

问题:

(1)关于近代物理,下列说法正确的是________。(填选项前的字母)

A.射线是高速运动的氦原子

B.核聚变反应方程表示质子

C.从金属表面逸出的光电子的最大初动能与照射光的频率成正比

D.玻尔将量子观念引入原子领域,其理论能够解释氦原子光谱的特征(2)如图,质量为M的小船在静止水面上以速率V0向右匀速行驶,一质量为m的救生员站在船尾,相对小船静止。若救生员以相对水面速率v水平向左跃入水中,则救生员跃出后小船的速率为______。(填选项前的字母)

考点:原子的核式结构模型:α粒子散射实验
题型:选择题

A


"In only six clays I lost seven pounds of weight. "
"Two full inches in the first three days!"
These are the kinds of statements used in magazine, newspaper, radio and television ads. , promising new shapes and new looks to those who buy the medicine or the device. The promoters of products say they can shape the legs, slim the face, smooth wrinkles, or in some other ways to add to beauty or desirability.
Often such products are nothing more than money-making things for their promoters. The results they produce are questionable, and some are dangerous to health.
To understand how these products can be legally promoted to the public, it is necessary to understand something of the laws covering their regulation. If the product is a drug, FDA (Food and Drug Administration)can require proof (证明) under the Food, Drug, and Cosmetic Act that is safe and effective before it is put on the market. But if the product is a device, FDA has no authority to require pre-marketing proof of safety or effectiveness. If a product already on the marker is a danger to health, FDA can request the producer or distributor to remove it from the market voluntarily, or it can take legal action, including seizure (查封) of the product.
One notable case a few years ago involved an electrical device called the Relaxacisor, which had been sold for reducing the waistline. The Relaxacisor produced electrical shocks to the body through contact pads. FDA took legal action against the distributor to stop the sale of the device on the grounds that it was dangerous to health and life.
Obviously, most of the devices on the market have never been the subject of court proceedings (法律诉讼), and new devices appear continually. Before buying, it is up to the consumer to judge the safety or effectiveness of such items.

The author intends to ______.

A.make consumers aware of the promoters’ false promises

B.show the weakness of the law on product safety

C.give advice on how to keep young and beautiful

D.introduce the organization of FDA

题型:选择题

关于四大洋叙述正确的是[ ]

A.太平洋和欧洲相邻

B.印度洋的平面轮廓呈S形

C.太平洋底有世界上最深的海沟—马里亚纳海沟

D.北冰洋是唯一有冰山的洋

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早在1957年马寅初的《新人口论》就预见到人口众多会给我国社会的发展带来巨大的压力,主张计划生育,避免人口的无节制增长。据此完成1~2题。

1、早在1957年马寅初就预见到人口众多会给社会发展带来巨大压力,这说明[ ]

A、意识能够正确反映客观事物

B、意识是对事物本质和规律的反映

C、意识是对客观存在的正确反映

D、意识是对客观事物的如实“复制”

2、当年的《新人口论》遭到批判,而现在计划生育是我国的基本国策。这告诉我们[ ]

A、实践是认识的来源

B、实践是认识的目的和归宿

C、实践是认识发展的动力

D、实践是检验认识真理性的唯一标准

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治疗流感嗜血杆菌肺炎的首选抗菌药物是()

A.青霉素

B.红霉素

C.强力霉素

D.链霉素

E.氨苄西林

题型:选择题

战略规划是企业发展战略的核心和基本内容,是为了实现发展目标而制定的具体规划,表明企业在每个发展阶段的具体目标、工作任务和实施路径。

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