如图所示的滑轮（不计摩檫），把重150N的物体匀速提起，所用拉力为100N，则关于该滑轮的说法中错误的是（　　）

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阅读下文，回答问题。

苏七块

冯骥才

      ①苏大夫本名苏金散，民国初年在小白楼一带，开所行医，正骨拿踝，天津卫挂头牌，连洋人赛马，折胳膊断腿，也来求他。

      ②他人高袍长，手瘦有劲，五十开外，红唇皓齿，眸子赛灯，下巴儿一绺山羊须，浸了油似的乌黑锃亮。张口说话，声音打胸腔出来，带着丹田气，远近一样响，要是当年入班学戏，保准是金少山的冤家对头。手下动作更是“干净麻利快”，逢到有人伤筋断骨找他来，他呢？手指一触，隔皮截肉，里头怎么回事，立时心明眼亮。忽然双手赛一对白鸟，上下翻飞，急如闪电，只听“咔嚓咔嚓”，不等病人觉疼，断骨头就接上了。贴块膏药，上了夹板，病人回去自好。倘若再来，一准是鞠大躬谢大恩送大匾来了。

      ③人有了能耐，脾气准特色。苏大夫有个特色的规矩，凡来瞧病，无论贫富亲疏，必得先拿七块银元码在台子上，他才肯瞧病，否则决不搭理。这叫嘛规矩？他就这规矩!人家骂他认钱不认人，能耐就值七块，因故得个挨贬的绰号叫做：苏七块。当面称他苏大夫，背后叫他苏七块，谁也不知他的大名苏金散了。

      ④苏大夫好打牌，一日闲着，两位牌友来玩，三缺一，便把街北不远的牙医华大夫请来，凑上一桌。玩得正来神儿，忽然三轮车夫张四闯进来，往门上一靠，右手托着左胳膊肘，脑袋瓜淌汗，脖子周围的小褂湿了一圈，显然摔坏胳膊，疼得够劲。可三轮车夫都是赚一天吃一天，哪拿得出七块银元？他说先欠着苏大夫，过后准还，说话时还哼哟哼哟叫疼。谁料苏大夫听赛没听，照样摸牌看牌算牌打牌，或喜或忧或惊或装作不惊，脑子全在牌桌上。一位牌友看不过去，使手指指门外，苏大夫眼睛仍不离牌。“苏七块”这绰号就表现得斩钉截铁了。

      ⑤牙医华大夫出名的心善，他推说去撒尿，离开牌桌走到后院，钻出后门，绕到前街，远远把靠在门边的张四悄悄招呼过来，打怀里摸出七块银元给了他。不等张四感激，转身打原道返回，进屋坐回牌桌，若无其事地接着打牌。

      ⑥过一会儿，张四歪歪扭扭走进屋，把七块银元“哗”地往台子上一码。这下比按铃还快，苏大夫已然站在张四面前，挽起袖于，把张四的胳膊放在台予上，捏几下骨头，跟手左拉右推，下顶上压，张四抽肩缩颈闭眼呲牙，预备重重挨几下，苏大夫却说：“接上了。“当下便涂上药膏，夹上夹板，还给张四几包活血止疼口服的药面子。张四说他再没钱付药款，苏大夫只说了句：“这药我送了。”便回到牌桌旁。

      ⑦今儿的牌各有输赢，更是没完没了，直到点灯时分，肚子空得直叫，大家才散。临出门时，苏大夫伸出瘦手，拦住华大夫，留他有事。待那二位牌友走后，他打自己座位前那堆银元里取出七块，往华大夫手心一放。在华大夫惊愕中说道：

      ⑧“有句话，还得跟您说。您别以为我这人心地不善，只是我立的这规矩不能改!”

      ⑨华大夫把这话带回去，琢磨了三天三夜，到底也没琢磨透苏大夫这话里的深意。但他打心眼儿里钦佩苏大夫这事这理这人。

请补全以下求不等式﹣2x²﹣4x＞0的解集的过程．

①构造函数，画出图象：根据不等式特征构造二次函数y=﹣2x²﹣4x；并在下面的坐标系中（图1）画出二次函数y=﹣2x²﹣4x的图象（只画出图象即可）．

②求得界点，标示所需，当y=0时，求得方程﹣2x²﹣4x=0的解为多少？；并用锯齿线标示出函数y=﹣2x²﹣4x图象中y＞0的部分．

③借助图象，写出解集：由所标示图象，可得不等式﹣2x²﹣4x＞0的解集为﹣2＜x＜0．请你利用上面求一元一次不等式解集的过程，求不等式x²﹣2x+1≥4的解集．

阅读下面短文，掌握其大意，然后从1～15各题所给的A、B、C和D项中，选出最佳选项。

Life is full of heartaches, joys and many lessons to learn. However, it is up to us to decide how we begin and end it. I 1 believe that every day when we 2 up in the morning, we should be 3 of the fact that time is slipping away fast and violently like sand in an hourglass(沙漏).

We can choose to free our minds of whatever lies ahead and prevent life from limiting our vision of the future or 4 us from achieving what we are tending to become. Although, the journey of life will not always be 5 because at times we will meet many challenges, we should never despair but 6every moment. Every choice or decision we make should be pursued7.

Despite the fact that at some point life present to us countless possibilities, it is those challenging times that always8us towards realizing our purpose in life and greatness.

Sometimes life’s 9can make us feel that the current situation we face conflicts with how we’d like to keep in life. However, it is only if we allow life’s challenges to 10 our direction and decision that we may never  11realize our potential. We should not allow life’s challenges to limit our reach for a better future. If we take control of today to our12by leaving no stone unturned, tomorrow is already reshaped for the better.

Life is always filled with uncertainties. It is on this basis that we should not13time on small things and with people who take us for  granted. We ought to learn from experiences and use them to reset our14and goal in life. This way, we will be better off, more successful. We should never waste any time or15and this can only be actualized once we realize that life is full of possibilities.