READY or not, the college application season has begun. There are two main kinds of early admissions programs: Early Action and Early Decision.

    Early Action is a great choice for the well-prepared student. Students apply early, and are allowed to apply under an Early Action program to as many colleges as they choose. The biggest advantage for students is that colleges let them know early – in most cases, before Jan 1. Roughly 15 percent of colleges and universities offer an Early Action option(选择). Oct 15 is now the first deadline for many colleges and universities. This movement toward earlier deadlines is especially popular in the Southeast, with many of the large public universities leading the way. North Carolina State University, the University of South Carolina and the University of Georgia all have an Oct 15 Early Action deadline.

    Early Decision is a promise that cannot be reversed. Students who are accepted must take back their other applications and should attend that school. Students are allowed to apply to just one school under an Early Decision program. Early Decision deadlines are in early November, with colleges letting students know by mid-December. Many students believe that they are more likely to be accepted if they apply for Early Decision, but it actually depends.

       In some cases there is big increase in students being accepted, and at other colleges it is not that big at all. Generally, the strongest students are applying early. Athletes and students with focused interests are encouraged to apply for Early Decision.

You should ask questions p____ with “Excuse me” at first.

已知四棱柱ABCD﹣A₁B₁C₁D₁的底面ABCD是边长为2的菱形，AA₁=2$\sqrt{3}$，BD⊥A₁A，∠BAD=∠A₁AC=60°，点M是棱AA₁的中点．

（Ⅰ）求证：A₁C∥平面BMD；

（Ⅱ）求点C₁到平面BDD₁B₁的距离．

已知NO₂和N₂O₄可以相互转化：2NO₂（g）⇌N₂O₄（g）△H＜0．现将一定量NO₂和N₂O₄的混合气体通入体积为1L的恒温密闭容器中，反应物浓度随时间变化关系如图．下列说法错误的是（　　）

阅读下文，回答相关问题。

                                                                                                     守住孤单
         ①电影《梅兰芳》刻画了京剧艺术大师梅兰芳截然不同的两面人生：舞台上神采飞扬，光鲜亮丽；生活中却木讷寡言，不谙世事，甚至不懂幽默。在其经纪人邱如白看来，正是由于平日里的这种孤单，才使得梅兰芳事业高度专一、成就卓然不群。
         ②孤单耶？寂寞也。“古来圣贤皆寂寞”。历代成大器者，几乎无一不承受着自己那份孤单。周文王被拘禁而推演出《     》，孔子在困厄中著述《春秋》，屈原被放逐写出《       》，左丘明双目失明作成《国语》，________________ ,_________________。这些往圣先贤的旷世之才、盖世之功、万世之名，都是在磨难痛苦后的长期孤单中孕生的。不过他们的孤单均带有外在强制性，是难以抗拒状态下的无可奈何。但后来许多仁人志士悟透了孤单的真谛，便躲避尘世、主动隐居、自寻孤单。正如诸葛亮所说：“非淡泊无以明志，________________”
         ③孤单与其说是一种闲静，不如说是一种煎熬。它需要远离奢华，远离功名，甚至远离感官和肉体的幸福。古人宁静孤单难，今人宁静孤单更难。市场经济大潮营造了一个缤纷绚丽的世界。这个信息过剩、眼花缭乱的时代，诱惑太多、浮躁日盛，守住孤单实在不易。
         ④交往甚广者难守孤单——这样的人整天忙着应酬，马不停蹄地穿梭于各种酒场饭局之间，左右逢源，八面玲珑，无所不能企及，仿佛跟谁都可以套瓷，把驾驭人脉关系当资本，以结织官款星腕为荣耀，将通达人情世故作美誉，结果交际圈越大越是心无定所，神不守舍。
        ⑤物欲甚重者难守孤单——吃要星级酒楼，穿要品牌档次，住要豪华寓所。他们也许会得到暂时好处，但就其一生而言，却是得不偿失。
        ⑥守住孤单，不是倡导过古人那种田园牧歌、闲云野鹤式的生活，而是希望人们不染浮躁，保持一份心灵的恬静。
        ⑦当然，孤单不是孤僻、孤冷、孤傲，不是旁若无人的自恃清高，也不是心灵封闭的孤芳自赏。我们追求的孤单，应当是超凡脱俗的豁达、心如止水的意境。孤单者须有云消气度松柏精神，不以物喜，不以己悲。在浮躁的社会生态环境中，孤单是修身明志的心灵空调。做自己命运的船长，当自己灵魂的舵手，就得守住孤单。