题干

已知:2CH3COCH3(l) CH3COCH2COH(CH3)2(l)。取等量CH3COCH分别在0℃和20℃下反应,测得其转化率(α)随时间(t)变化的关系曲线如图所示。下列说法正确的是(   )

A:曲线Ⅱ表示20℃时的转化反应

B:升高温度能提高反应物的平衡转化率

C:在a点时,曲线Ⅰ和Ⅱ表示反应的化学平衡常数相等

D:化学反应速率的大小顺序为:d>b>c

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D

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    A research has shown that nearly 90 percent of traffic accidents are caused by human errors. So our aim is a fully autonomous car that gets rid of the cause of most accidents: the driver. Researcher Hodgson points out, “For safety, the faster you can remove humans, the better, even if there are unfortunately a few accidents from new causes. It s a question of balancing the number injured or killed by autonomous vehicles with the people whose lives are potentially saved.”

    It’s an idea that Elon Musk, chief executive of electric car company Tesla Motors, has long believed. His company are determined to be the first to deliver a fully autonomous vehicle to consumers. Last year, Musk announced that Tesla’s 2017 goal was “to do an example drive of full autonomy all the way from LA to New York…and have the car park itself.”

    However, even Tesla admits that there are problems to overcome—the software needs further validation and the appropriate regulatory approval needs to be in place. Indeed, recent crashes of Tesla vehicles and Google cars confirm that the software isn’t ready yet.

    The UK government appears committed to encouraging the development of autonomous vehicles. It’s supporting four city trials, publishing the Modem Transport Bill to reduce red tape around their introduction and adapting the legal system to take into account problems such as insurance liability when a human isn’t in control of a vehicle.

    The insurance industry is similarly eager to help increase autonomy in cars. As the Association of British Insurers (ABI) points out, “More than 90 per cent of road accidents are caused by human error.” This costs motor insurers a shocking £20m per day in claims.