题干

用地壳中某主要元素生产的多种产品在现代高科技中占有重要位置,足见化学对现代物质文明的重要作用。例如:计算机芯片的主要成分是____;光导纤维的主要成分是____;过氧化钠在呼吸面具或潜水艇中作为氧气的,其CO2反应的化学方程式为____;红热的铁跟水蒸气反应,反应的化学方程式为____;工业上用电解氯化钠溶液的方式制取氯气,反应的化学方程式为____。
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C

    This month, Germany's transport minister, Alexander Dobrindt, proposed the first set of rules for autonomous vehicles(自主驾驶车辆). They would define the driver's role in such cars and govern how such cars perform in crashes where lives might be lost.

    The proposal attempts to deal with what some call the “death valley” of autonomous vehicles: the grey area between semi-autonomous and fully driverless cars that could delay the driverless future.

    Dobrindt wants three things: that a car always chooses property(财产) damage over personal injury; that it never distinguishes between humans based on age or race; and that if a human removes his or her hands from the driving wheel — to check email, say — the car's maker is responsible if there is a crash.

    “The change to the road traffic law will permit fully automatic driving,” says Dobrindt. It will put fully driverless cars on an equal legal footing to human drivers, he says.

    Who is responsible for the operation of such vehicles is not clear among car makers, consumers and lawyers. “The liability(法律责任) issue is the biggest one of them all,” says Natasha Merat at the University of Leeds, UK.

    An assumption behind UK insurance for driverless cars, introduced earlier this year, insists that a human “ be watchful and monitoring the road” at every moment.

    But that is not what many people have in mind when thinking of driverless cars. “When you say ‘driverless cars', people expect driverless cars.”Merat says. “You know — no driver.”

    Because of the confusion, Merat thinks some car makers will wait until vehicles can be fully automated without operation.

    Driverless cars may end up being a form of public transport rather than vehicles you own, says Ryan Calo at Stanford University, California. That is happening in the UK and Singapore, where government-provided driverless vehicles are being launched.

    That would go down poorly in the US, however. “The idea that the government would take over driverless cars and treat them as a public good would get absolutely nowhere here,” says Calo.