精刨代刮，通常精刨余量在（）mm左右。A、0.1～0.5 B、0.3～0.5 C、0

蜡烛燃烧生成______和______．蜡烛燃烧时的火焰可以分成三层，由里向外依次是______、______、______．其中______的温度最高．

利用铜、锌片和200mL稀硫酸组成原电池，将化学能转化为电能，当硫酸全部被消耗完时，铜片上 * * 生3.36L（标准状况）气体．试计算：

（1）导线里通过的电子的物质的量为______；

（2）原稀硫酸溶液中H⁺的物质的量浓度为______．

    There's something rotten in Rio and the smell is coming from the huge stacks of rubbish pried up on sidewalks all over the city. Rio's street sweepers chose the carnival holiday to demand better salaries. Their wages start at roughly $400 a month.

There could hardly be a better time for them to prove their importance. The streets were left a mess after hundreds of carnival parades and now, rubbish pries up in both poor and uptown neighbourhoods and in tourist areas like Ipanema or Copacabana beach.                                                                                                                                         

The president of Rio's rubbish collecting company has even appealed to the population to store rubbish at home whenever possible. He says 30% of the city's sweepers have gone on strike. Some of those who have been working have been threatened by the strike movement so now the police has been deployed alongside rubbish collectors to keep them sage as they go about their business.

The strike has divided opinions in Rio. On social media, many support the sweepers' demands for better salaries. Others say they are opportunists and the situation is a big embarrassment to the city.

But Brazil's culture of littering the streets doesn't help. A video that went viral online shows that even authorities have a problem with that. Rio's mayor, Eduardo Paes, is seen throwing what seemed to be the rest of an apple on the sidewalk--and now promised to impose himself a fine for his wrongdoing. His government recently created a programme to keep Rio's residents from littering the streets.

小题1:Rio's street cleaners go on strike to

A．prove their importance

B．threaten the government

C．ask for higher salaries

D．appeal to the public not to litter小题2:The reason why the police are involved is that __

A．the police are called out to put down the riot

B．the police are required to protect some cleaners

C．the police are to collect rubbish for the time being

D．the police are sent to arrest people who litter around小题3:The author's attitude to Brazil's culture of littering is __

A．hopeless

B．approving

C．critical

D．optimistic小题4: The purpose of writing the passage is to __

A．criticize, street sweepers of Rio for misusing their rights

B．call attention to the embarrassing situation of Rio

C．describe the effect or the strike on people

D．inform people of the present situation of Rio

臧克家40年代中期政治讽刺诗的代表有（）和（）两个集子。

采煤工作面严禁使用木支柱（极薄煤层除外）和金属摩擦支柱支护。