题干

设集合A={(x,y)||x|+|y|≤2},B={(x,y)∈A|y≤x2},从集合A中随机地取出一个元素P(x,y),则P(x,y)∈B的概率是(  )

A:112

B:1724

C:23

D:56

上一题 下一题 0.0难度 选择题 更新时间:2012-04-10 04:27:45

答案(点此获取答案解析)

B

同类题2

阅读下文,回答问题

“强制”垃圾分类能否真正改变生活?

【事件】

近日,国务院办公厅转发国家发展改革委、住房和城乡建设部《生活垃圾分类制度实施方案》。《方案》提出,到2020年底要基本建立垃圾分类相关法律法规和标准体系,形成可复制可推广的生活垃圾分类模式,并在46个城市实施生活垃圾强制分类。

【百家争鸣】

所谓强制,隐含的意思就是界定了垃圾分类的责任,明确了我们每个人都是垃圾的产生者,要对这些垃圾负责,否则就要受到一定的约束。但根据国内的现实情况,估计短时间内可能还是会将强制性手段与激励性措施结合起来,双管齐下,让居民尽快养成垃圾分类的习惯。

——清华大学环境学院教授刘建国

近些年,垃圾分类的知识得到了广泛宣传,大家的认识也提高了。刚开始做垃圾分类时,主要还是提可回收物,现在已经细化为可回收物、家庭有害垃圾和厨余垃圾,这与国际上先进的国家基本一致。

——中国城市建设研究院总工程师徐海云

为什么(垃圾)焚烧这么盛行,分类做不起来?这由于“懒政”。烧是最省事的,只要建一个垃圾焚烧厂一股脑拉过去烧了就完了。地方政府哪怕拿出垃圾焚烧10%的钱,用于垃圾分类,也会大幅度减少垃圾处理量。

——中国政法大学环境资源法研究所所长王灿发

垃圾本身是消费行为的产物,既要从垃圾的产生源头控量,如治理过度包装,对特殊行业如快递实行包装物强制回收和综合利用,也要建立垃圾循环利用,从生产与消费的过程中提取成本,纳入到相关经济政策中调节,真正让垃圾处理变成产业。

——《武汉晚报》时评作者木须虫

眼下关键的问题在于,我们还没有设计出比较科学的垃圾分类法则,也就无法实施高强度、高频率的国民教化。现行的小学教材里,就找不到系统规范的垃圾分类教材内容,这是我们基础教育的缺失。

——网友

我们的惯常思路是喜欢“运动式治理”,但垃圾分类却需要潜移默化的自觉行动,而社会观念的转变更需要刚性的法规和监管制约。

——《羊城晚报》首度评论员阅尽

【他山之石】

日本垃圾分类之严格和细致,堪称榜样。日本的垃圾分可燃、不可燃、资源垃圾三大类,其中资源垃圾又分纸张、塑料、玻璃、金属等。日本各地对垃圾分类的具体规定稍有差异,但基本上都细分到10种以上。

能将繁琐的规定一以贯之,关键在于垃圾投放、收集和运输全程各个环节的相互配合。在日本,不同种类的垃圾要按不同的日子扔。一般来说,每个生活小区每周有两天集中扔餐厨等可燃垃圾,一天扔纸张等资源垃圾。即使在盛夏,生活垃圾发酵发臭,不到日子也只能放置在家中。等到回收资源垃圾的当天,垃圾收集站会摆开一列收集箱,分别盛放金属、塑料、玻璃等。环卫部门装运垃圾多次往返,每趟只拉一种垃圾,避免“混装混运”。日本多数生活小区并没有专职的保洁员,垃圾分类主要靠居民自觉。

同类题3

阅读理解

      Last year in the UK at least 45 people died and 900 more were injured (受伤的) in car accidents where drivers were using their mobile phones.Yet many people continue to use them while driving even though it’s dangerous.

      Research has shown that it is difficult to concentrate on (专注于) driving and talking at the same time.It can even be more dangerous than driving after drinking too much. A recent study found that when drivers were talking on their mobile phones,their stopping times were 30 percent slower than when they had drunk too much—and nearly 50 percent slower than when they were driving normally. It also found that drivers talking on mobile phones were less able to control their cars than drunk drivers.

      And talking isn’t even the most serious problem, but texting is. Unbelievably, another recent study reported that 22% of adults admitted (承认) they had sent a text message while driving at least once in the past month. An average (平均的) text message takes 90 seconds to write and send. That means for one and a half minutes a driver is looking at their phone’s screen and not at the road. The arrival of new smart phones such as the iPhone will only make things worse as they will allow users to do more things than ever before.

      Using a mobile phone while driving puts others’ lives at risk. No matter how well we drive,if another driver is not careful,we are put in danger by their actions. Such drivers are selfish,careless and should have their driving licences (驾照) cancelled (撤销).

      There is no doubt that mobile phones can be fun and are useful,especially when you’re in trouble.But there is no need to use them while driving. Just wait until you stop or you will probably get into trouble of your own.