把分别充满红棕色的NO₂气体和无色的H₂的集气瓶按照如图A、B两种方式放置，然后把两瓶中间的玻璃片抽走，使两瓶口密合在一起（不要振荡），可观察到A中两瓶气体的颜色很快趋于一致（两气体不反应），而B中需要很长时间才能达到同样的效果．

由此可以得出的结论有：

（1）____；（2）____ ．

   Short and shy, Ben Saunders was the last kid in his class picked for any sports team. "Football, tennis Cricket — anything with a round ball, I was useless." he says now with a laugh. But back then he was the object of jokes in school gym classes in England’s rural Devonshire.
It was a mountain bike he received for his 15^th birthday that changed him. At first the teen went biking alone in a nearby forest. Then he began to cycle along with a runner friend. Gradually, Saunders set his mind building up his body, increasing his speed, strength and endurance. At age 18, he ran his first marathon.
   The following year, he met John Ridgway, who became famous in the 1960s for rowing an open boat across the Atlantic Ocean. Saunders was hired as an instructor at Ridgway’s school of Adventure in Scotland, where he learned about the older man’s cold-water exploits (成就). Intrigued, Saunders read all he could about Arctic explorers and North Pole expeditions, then decided that this would be his future. Journeys to the Pole aren’t the usual holidays for British country boys, and many people dismissed his dream as fantasy. "John Ridgway was one of the few who didn’t say, ’You are completely crazy,’" Saunders says.
   In 2001, after becoming a skilled skier, Saunders started his first long-distance expedition toward the North Pole. He suffered frostbite, had a closer encounter (遭遇) with a polar bear and pushed his body to the limit.
   Saunders has since become the youngest person to ski alone to the North Pole, and he’s skied more of the Arctic by himself than any other Briton. His old playmates would not believe the transformation.
   This October, Saunders, 27, heads south to explore from the coast of Antarctica to the South Pole and back, an 1800-mile journey that has never been completed on skis.

一位同学的研究性学习报告中，有以几个小标题：“默片时代”、“有声时代”、“黑白时代”、“彩色时代”。该同学的研究课题最有可能是(   )

阅读理解

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.