题干

将一颗骰子投掷两次,第一次出现的点数记为,第二次出现的点数记为,
设两条直线l1axby=2,l2x+2y=2平行的概率为P1,相交的概率为P2
试问点(P1P2)与直线l2x+2y=2的位置关系是(   )

A:P在直线l2的右下方

B:Pl2直线的左下方

C:P在直线l2的右上方

D:P在直线l2

上一题 下一题 0.0难度 选择题 更新时间:2016-07-18 11:35:13

答案(点此获取答案解析)

B

同类题2

阅读下面的文章,完成下列各题。

激发“到此一游”的文明耻感

李浩燃

       ①埃及卢克索神庙有着3000多年历史的浮雕上,刻划着汉字“丁××到此一游”。近日,有人在微博上贴出这样一幅刺目的照片,发布者“无地自容”的心情,也成为很多网友的一致感受。

       ②“没到过卢克索,就不算到过埃及。”神庙与汉字,两大文明竟以如此方式相遇,实在让人尴尬。不管是真心喜爱、跟风模仿还是年幼无知、出于炫耀,这种行为不仅污损了人类文明的瑰宝,也为中国游客添了一笔不良记录。

       ③相对大多数中国游客的有序有礼,少数人的不良表现更容易被放在公共外交的聚光灯下。不讲卫生、不遵守公共秩序、踩踏黄线、在飞机上争夺行李架空位……因为这些行为,中国游客甚至在国外一家市场调研机构的调查中,名列“最差游客榜”第二名。当中国出境旅游人数从2000年的1000万人次快速增长至2012年的8300万人次,“每个人都是一部中国读本”,这句提醒更有特殊含义。

       ④“到此一游”的风波,理应成为反思文明素养的契机。面对刻字,现场中国游客莫不感觉羞愧,甚至连导游也赶紧走开。微博热议、媒体讨论中,惭愧、耻辱的情绪,谴责、反省的主调,也让人看到整个社会对文明素质的强烈吁求、一个国家文明意识的自我审思。当事孩子的父母也主动联系媒体,流下忏悔泪水,坦言“孩子犯错误,主要责任在大人,是我们监护不到位,平时教育做得不好”,公开道歉。未成年人犯错在所难免,应予以必要宽容并助其改正,但整个社会则应以此为镜、自我检视。

       ⑤的确,“到此一游”远涉重洋,也是国内不文明言行的不自觉“输出”。从被刻字弄得遍体鳞伤的长城,到赫然出现在故宫大水缸上的涂划,都是孩子耳濡目染的“活教材”。习惯了乱闯红灯,出了国可能也会“红绿色盲”;***声喧哗,在国外也难以主动调低音量。从这个角度说,文明习惯的养成不分海内外,文明素养的提升,更需要每个人的日常践行。

       ⑥有人说,最好的“到此一游”,是把旅途中所有的美好都刻在心上。而提升文明素养,也需在心上刻下这让人蒙羞的“到此一游”。在拥堵的公路上随意并道时,在地铁的长队里加塞插队时,在逃票成功洋洋得意时,在网络空间掐架骂娘时,在网络空间掐架骂娘时,,,这几个字就该闪动警示之光,提醒你触碰到了文明的红线。谨记“到此一游”激发的文明耻感,以此自戒自省,以此校言校行,整个社会的文明程度才能迈进一步。

       ⑦今日中国,吃饭穿衣已经不是问题,甚至海外奢侈品商店促销都会挂上汉语海报。然而,很多人也感觉,“两手满当当,心中空荡荡”。的确,现代化的过程中,怎能少了人的行为举止、思想意识的现代化?国务院会议倡导“健康文明旅游方式”,政府机构出台“文明行为指南”,这些都让人看到,在社会管理者那里,文明素养、人的素质,已越来越成为“发展的必修课”。

       ⑧同样是神庙,雅典阿波罗神庙的一块石板上,刻着这样的铭文:认识你自己。反思埃及神庙刻字事件,以此为契机省察自我文明素养,才能在国际交往中赢得尊敬,更让我们在文明复兴之路上“递进一层”。

(选自2013.5.27《人民日报》)

同类题3

阅读下列短文,从每题所给的四个选项中,选出最佳选项。
C
    There are an extremely large number of ants worldwide. Each individual ant hardly weigh anything, but together they weigh almost the same as all of mankind. They also live nearly everywhere, except on frozen mountain tops or around the Antarctic. For animals their size, ants have been surprisingly successful, largely due to their wonderful social conduct.
    In groups that vary in size from a few hundred to tens of millions, they organize their lives with a clear distribution of labor. Even more amazing is how they achieve this level of organization. While we use sound and sight to communicate, ants depend mostly on pheromone (信息素), which is a kind of chemical released by individuals and smelled or tasted by fellow members of a group. When an ant finds food, it produces a pheromone that will lead others straight to where the food is. When an ant comes under attack or is dying, it sends out an alarm pheromone to warn the whole group to prepare for a defensive fight.
    In fact, when it comes to the art of war, ants have no equal. They are completely fearless and will take on an animal much larger than themselves, attacking in large groups and beating their target. They show so much devotion to their group that not only soldier ants but also worker ants will sacrifice their lives to help defeat an enemy.
    United and devoted, these little animals have survived on the earth for more than 140 million years, far longer than dinosaurs. Because they think as one, they have a united intelligence greater than you would expect from one small individual ant.