I do not know why I came to the decision to become a loser, but I know I made the choice at a young age. Sometime in the middle of fourth grade, I stopped 1. By the time I was in seventh grade, I was your2degenerate (颓废): lazy, rebellious, and disrespectful. I had lost all social 3 I terminally (不可救药的) followed, what was fashionable.

    Not long after that, I dropped out of school and 4 my downward spiral. Hard physical labor was the5for the choices I made as an adolescent. At the age of twenty-one, I was6 lost and using drugs as a way to deal with the fact that I was uneducated and7 in a dead-end job carrying roof materials up a ladder all day.

    But now I believe in do-overs, in the8 to do it all again. And I believe that do-overs can be made at any point in your life, if you have the right 9 Mine came from a10source.

    It was September 21, 2002, when my son Blake was born. It's funny that after a life of 11responsibility, now I was in charge of something so 12Over the years, as I grew into the title of Dad, I began to learn something about myself13 Blake and I were both learning to walk, talk, work, and play for the first time. I began my do-over.

    It took me almost three years to learn 14to read. I started with my son's books. Over and over, I practiced reading books to him15 I remembered all the words in every one of them. I began to wonder if it was possible for me to go back to school. I knew I wanted to be a good role model,16 after a year-and-a-half and a lot of hard work, I passed my GED test on my son's fourth birthday. This may not sound like 17and I am not trying to get praise for doing something that should have been done in the first place, but all things considered it was one of the18days in my life. Today, I am a full-time college student, studying to become a sociologist.

    Growing up, I19 heard these great turn-around stories of triumph over shortcomings. But I never thought they applied to me. Now I believe it is a (an)20anyone can make: To do it all over again.

阅读下面的文字，完成小题。

平凡的色彩，不平凡的发明

    2014年，日本科学家赤崎勇、天野浩和日裔美籍科学家中村修二，由于对蓝光发光二极管研发所作出的突出贡献而获得诺贝尔物理学奖。那么，蓝光发光二极管究竟凭借着什么样的魅力获得诺贝尔奖的垂青呢？

传统光源的困境

    照明对于人类文明的重要性不言而喻。自爱迪生发明白炽灯之后，荧光灯、蒸汽灯等传统光源相继出现，这些传统光源能够出色地完成照明任务，但也存在着明显的缺陷。如白炽灯需要将灯丝加热到上千度的高温，但电能大都转化成了热能，转化成光能的很少。荧光灯利用汞原子辐射的紫外线，来激发荧光粉出光，虽然有较高的效率，但汞是有毒的，不环保。蒸汽灯通过对放电管产生高温电弧，使汞、钠蒸发，使其产生荧光，同样不环保。鉴于此，传统光源被称作“环境不友好”的光源。

A          

    受半导体技术的启发，科学家们开始研制发光二极管，寻求一种将电能直接转化成光的“电致发光”的照明方式。与传统光源不同，发光二极管它包含着复杂的结构，需要纳米尺度的精确工艺和复杂的技术，而且它的发光原理也是领先的，可以通过改变发光区的成分，改变光的颜色。发光二极管真的一点都不平凡。

    由于发光二极管的芯片非常地微小，所以可以在低电压（仅需几个伏特）、小电流（数毫安）下工作，即可获得足够高的亮度，并且通电后立即以稳定的状态发光，几乎没有明显的缺点，堪称“终极光源”。

姗姗来迟的蓝光

    发光二极管有如此多的优点，但为何没有成为我们的日常光源呢？这要从白光合成的原理说起。大家知道，太阳光的不同颜色，我们可以通过混合红、绿、蓝光模拟出来，因此红、绿、蓝被人们称为三原色。如果三原色缺了一种，那么我们就像色盲一样，看不到真实的色彩。

    因此，人类要想实现“半导体照明梦想”，就必须制作出能够发出类似这三原色光的发光二极管。遗憾的是，红光、绿光发光二极管在上个世纪70年代就已经成功研制出来，而蓝光发光二极管的研发却在很长时间内陷入了停滞。因为制备蓝光发光二极管所需要的材料——氮化镓，在很长时间里，科学家们只能得到粉末状的或者非晶态的氮化镓，而这种状态的氮化镓无法去做发光二极管。

    20世纪80年代后，氮化镓材料的质量已经有了明显的提高。赤崎勇、天野浩小组和中村修二，经过不懈的努力，分别利用不同的方法得到了镜面般光滑的氮化镓薄膜，完成了具有里程碑式意义的工作。1993年，随着第一颗蓝光LED首次由中村修二制成，半导体照明终于走出困境，踏上了快速发展之路。

B         

    蓝光发光二极管帮助人类实现半导体照明，节约了能源，但它带给人类的远远超出了“绿色环保”的范畴。今天，发光二极管的影响已经相当深远，能够覆盖到信息、通讯以及生命科学领域，在生活中，从宏伟的摩天大楼到精致的电子产品，到处都有发光二极管注入绚丽的色彩。

    蓝光发光二极管获奖，实至名归。

（选自《科学之谜》，有删改）

一个多边形内角和是一个四边形内角和的4倍，请求出这个多边形的边数．