题干

下列有关种群、群落、生态系统的叙述,正确的是(   )

A:种群密度是种群最基本的数量特征,调查动物种群密度常用的方法是样方法

B:群落演替过程中生物多样性逐渐降低,人类活动往往会改变演替的方向和速度

C:生物多样性比较高的生态系统相对稳定,这体现了生物多样性的直接价值

D:生态系统的稳态与自我调节能力大小有关,其稳态调节机制属于反馈调节

上一题 下一题 0.0难度 选择题 更新时间:2018-04-22 06:03:21

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D

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    US City Bans Texting while Walking

    Parents usually teach their children how to cross the street safely, by looking both ways for cars. But do they also teach them to put away their cell phones?

    The city of Honolulu, Hawaii wants everyone to learn that lesson____Beginning on October 24, you could be fined from $15 to $99 if you step into a Honolulu street while looking at your phone. Honolulu is the first major U. S. city to ban what is called "distracted (分散注意) walking. " It recently passed a law in a seven to two vote. The law says; “No pedestrian shall cross a street or highway while viewing a mobile electronic device. "____

    The law's creators hope it will lower the number of people hit and killed by cars in the city. Mayor Kirk Caldwell told Reuters news agency, "We hold the unfortunate distinction (区别) of being a major city with more pedestrians being hit in crosswalks, particularly our elders, than almost any other city in the country. "

    The law includes all electronic devices with screens: cell phones, tables, gaming devices, digital cameras and laptop computers____Pedestrians may use such devices in the street to call emergency services and rescue workers, such as firefighters and police officers.

    ____The Governors Highway Safety Association, or GHSA, says pedestrian deaths in the United States increase 25 percent between 2010 and 2015. That trend continued in 2016 with the number of pedestrian deaths rising to almost 6000, 11% higher than in 2015.

    If you still want to text while walking, you could avoid being fined in Honolulu (and be safer, in general) by using a voice-controlled digital(数字的) assistant such as Siri or Google Assistant____

A. The law does permit an exception.

B. Or you could just wait until you are again, safely, off the street.

C. You will be sentenced to prison while using cell phones in the street.

D. Pedestrian deaths have been increasing as the use of cell phones rises.

E. Texting while crossing the street will soon be banned in the city.

F. The law permits people to watch TV while crossing the street.

G. In other words, do not look at a screen when you cross the street or you could be fined.