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问题 单项选择题

有关心脏射血的描述，错误的是

A．血液射入动脉依赖于心室收缩
B．房室瓣关闭依赖于室内压高于房内压
C．房室瓣开放依赖于心房收缩
D．心室充盈主要依赖于心室舒张的抽吸作用
E．左、右心室的每搏输出量基本相等

答案

参考答案：C

选择题

在装有空气的密闭容器中，欲用燃烧的方法除去其中的氧气，又不能混入其他气体，可以使用的可燃物是（　　）

A．木炭

B．红磷

C．硫

D．蜡烛
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单项选择题

Residents of an apartment complex are considering two possible plans for collecting recyclable trash. Plan 1—Residents will deposit recyclable trash in municipal dumpsters located in the parking lot. The trash will be collected on the first and the fifteenth days of each month. Plan 2—Residents will be given individual containers for recyclable trash. The containers will be placed at the curb twice a week for trash collection.
Which of the following points raised at a meeting of the residents, if valid, would most favor one of the recycling plans over the other

A．Residents will be required to exercise care in separating recyclable trash from nonrecyclable trash.

B．For trash recycling to be successful, residents must separate recyclable bottles and cans from recyclable paper products.

C．Penalties will be levied against residents who fail to sort their trash correctly.

D．Individual recycling containers will need to be made of a p and durable material.

E．(E) Recyclable trash that is allowed to accumulate for two weeks will attract rodents.
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