${}_{27}^{60}$ Co是γ放射源， ${}_{27}^{60}$ Co可用于农作物的诱变育种，我国用该方法培育出了许多农作物新品种．对 ${}_{27}^{60}$ Co原子的叙述不正确的是（   ）

矩形线圈在匀强磁场中匀速转动产生的电动势如图，则(   )

补写出下列名篇名句中的空缺部分。

①《赤壁赋》中通过侧面描写表现洞箫声的凄切婉转的两句是“____，____”。

②李白的《蜀道难》中用“____，____”两句写出了蜀道的山之高，水之曲。

③《爱莲说》中与“近朱者赤，近墨者黑”形成对比，表现莲高洁品质的句子是“____，____”

阅读下文完成后面题目。
                                                                                                                                                “三好生”
        上小学的时候，从一年级到五年级，他从未当过“三好生”，也从未想过当“三好生”，尽管他成绩不错，表现也很好。
        村子很偏僻，村子的东北方向有一个军营，军营子女就成了学校里的一个特殊群体。他们比农家子弟“得宠”。村里的孩子只要不是很出色，很难引起老师的注意。他那时很自卑。
        五年级临放寒假时，学校照例在小操场上召开表彰会，“三好生”上台领奖往往是表彰会的高潮。校长在上面讲话，学生在下面说话，老师在后面吸烟，整个操场乱哄哄的什么也听不见，他坐在下面低着头想自己的心事。
        “要发奖了！”有人喊了一声，同学们的目光都聚到主席台上。被喊到的大都是军官子女，他很羡慕他们。当然仅仅是羡慕，即使夜里做一百零八个梦也不会梦见自己当“三好生”，他觉得“三好生”不是他这种人当的。直到旁边的“大棍”用胳膊肘捣他，“快！校长喊你到台上领奖，你是‘三好生’啦！”福星真的照到了自己的头上。他简直不知道该怎么办才好，激动得不知所措。
        “快去呀！”旁边的几个人叫道。
        就这样，在小学临近毕业的那个学期，他第一次被评上了“三好生”。
        领奖的时候，为了替农家子弟争回些面子，他走得郑重其事。到主席台上，他也像军官子女那样向校长敬了一个标准的少先队队礼。
        接下来，就该双手接奖状了。
        “你来干什么？”校长的神色奇奇怪怪，脸上没有一丝笑容。
        “我来……领奖呀。”他不明白，为什么校长对别的“三好生”笑容可掬，唯独对他冷冰冰的。他有些委屈。
        “领什么奖？！”校长一下子暴怒起来，“简直是胡闹！”
        他一下子懵了，“不是你喊我来领奖的吗？”
        “我叫你来领奖？”校长把“三好生”名单往他面前一递，“你看看，上面连你的名字都没有，我会叫你来领奖？”
        他听到身后传来了同学们的笑声。只听“大棍”一边笑一边大声嚷嚷：“哎，他信了！他信了！”
        这时他才知道自己被人捉弄了。他涨红了脸，眼泪似乎要奔涌而出了，他躲避着所有人的目光，转身就跑。
        他的班主任，一个不苟言笑、做事认真得近乎古板的人，走过来拦住他：“别走，这次‘三好生’有你呀。”
        全场一下子静了下来。
        班主任走到校长面前：“这次‘三好生’有他。怎么能没有呢？我明明记得有嘛。”
        校长生气地把名单递给他。他仔细地看了两遍，一拍脑门：“哎呀，你看我！我写名单的时候把他漏掉了，都怪我！”
        校长脸一沉，“胡闹！亏你平时那么认真，也能出这种错！现在怎么收场？”
        全场静得出奇。
        班主任把上衣口袋里的钢笔拿下来递到他手上：“没有奖状和红花了，这个奖给你吧！”班主任平时常穿一件蓝色中山装，上衣口袋里常常别着一支钢笔，钢笔的挂钩露在外面，在阳光下白灿灿的，常引得学生羡慕不已。要知道，那个时候对一个农村孩子来说，钢笔还是奢侈品啊。
        那个寒假，他过得既充实又兴奋。他拥有了第一支钢笔，最主要的是，这支笔代表着一种荣誉，是自己应该得到的奖品。他的自卑感一下子就消失了，从此和“三好生”结下了不解之缘，直到高中毕业，进入大学。
        他当时对班主任虽有感激，但更多的是埋怨，埋怨他一时的疏忽让自己在众人面前出了丑。要是领奖那天没有那令人难堪的一幕该有多好！他常这样想，并遗憾万分。从此以后，无论在校内校外，他见了班主任总觉得不自在，尽量躲着走。班主任一笑置之，待他如故。
        二十年后，他已是某中学的一位班主任。
        一天，他向妻谈起了往事，提到他当年的班主任，那个平时不苟言笑、做事认真得近乎古板的人。“你说，他那么认真的一个人，怎么能把我漏掉呢？”他感慨道。
        妻子笑吟吟地反问道：“他那么认真的一个人，怎么能单单把你漏掉呢？亏你现在还是班主任。”
        半晌无语。夜半，他披衣而起，两眼含泪，拿起信笺……                  

阅读下列短文：

Why College Is Not Home

           The college years are supposed to be a time for important growth in autonomy(自主性) and the development of adult identity. However, now they are becoming an extended period of adolescence, during which many of today’s students and are not shouldered with adult responsibilities.

For previous generations, college was decisive break from parental control; guidance and support needed help from people of the same age and from within. In the past two decades, however, continued connection with and dependence on family, thanks to cellphones, email and social media, have increased significantly. Some parents go so far as to help with coursework. Instead of promoting the idea of college as a passage from the shelter of the family to autonomy and adult responsibility, universities have given in to the idea that they should provide the same environment as that of the home.

            To prepare for increased autonomy and responsibility, college needs to be a time of exploration and experimentation. This process involves “trying on ” new ways of thinking about oneself both intellectually(在思维方面) and personally. While we should provide “safe spaces” within colleges, we must also make it safe to express opinions and challenge majority views. Intellectual growth and flexibility are fostered on debate and questioning.

Learning to deal with the social world is equally important. Because a college community(群体) differs from the family, many students will struggle to find a sense of belonging. If students rely on administrators to regulate their social behavior and thinking pattern, they are not facing the challenge of finding an identity within a larger and complex community.

Moreover, the tendency for universities to monitor and shape student behavior runs up against another characteristic of young adults: the response to being controlled by their elders. If acceptable social behavior is too strictly defined(规定) and controlled, the insensitive or aggressive behavior that administrators are seeking to minimize may actually be encouraged.

          It is not surprising that young people are likely to burst out, particularly when there are reasons to do so. Our generation once joined hands and stood firm at times of national emergency. What is lacking today is the conflict between adolescent’s desire for autonomy and their understanding of an unsafe world. Therefore, there is the desire for their dorms to be replacement homes and not places to experience intellectual growth.

Every college discussion about community values, social climate and behavior should include recognition of the developmental importance of student autonomy and self-regulation, of the necessary tension between safety and self-discovery.