题干

下列实验操作正确的是(   )

A:将氢氧化钠固体放在滤纸上称量

B:用10 mL量筒量取8.58 mL蒸馏水

C:用加热高锰酸钾分解制O2时,试管口应略向上倾斜

D:配制一定浓度稀硫酸时,应将浓硫酸慢慢加入水中,边加入边搅拌

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答案(点此获取答案解析)

D

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根据短文内容,选择最佳答案。

Forget Cyclists, Pedestrians are Real Danger

We are having a debate about this topic. Here are some letters from our readers.

■ Yes, many cyclists behave dangerously. Many drivers are disrespectful of cyclists But pedestrians are probably the worse offenders.

People of all ages happily walk along the pavement with eyes and hands glued to the mobile phone, quite unaware of what is going on around them. They may even do the same thing while crossing a road at a pedestrian crossing or elsewhere. The rest of us have to evade (避让) them or just stand still to wait for the unavoidable collision.

The real problem is that some pedestrians seem to be, at least for the moment, in worlds of their own that are, to them, much more important than the welfare of others.

——Michael Horan

■ I loved the letter from Bob Brooks about cyclists (Viewpoints, May 29). I am afraid they seem to think they own the roads.

I was walking across Altrincharn Road one morning when a cyclist went round me and on being asked what he was doing he shouted at me.

The government built a cycle lane on the road but it is hardly used.

The police do nothing. What a laugh they are!

The cyclists should all have to be made to use the cycle lanes and wear helmets, fluorescent (发荧光的)jacket and tights at night and in the morning. They should pay some sort of tax and be fined for not wearing them.

——Carol Harvey

■ Cyclists jump on and off pavements (which are meant for pedestrians), ride at speed along the pavements, and think they have a special right to go through traffic lights when they are on red.

I was almost knocked down recently by a cyclist riding on the pavement when there was a cycle lane right next to him.

Other road users, including horse riders, manage to obey the rules so why not cyclists?

It's about time they had to be registered and insured, so when they do hit a pedestrian or a vehicle, or cause an accident, at least they can be traced and there might be an opportunity to claim.

——JML

Write to Viewpoints of the newspaper.