B

    Here is an astonishing and significant fact: Mental work alone can’t make us tired. It sounds absurd. But years ago, scientists tried to find out how long the human brain could labor without reaching a stage of fatigue (tiredness). To the amazement of these scientists, they discovered that blood passing through the brain, when it is active, shows no fatigue at all! If we took a drop of blood from a day laborer, we would find it full of fatigue toxins (毒素) and fatigue products. But if we took blood from the brain of an Albert Einstein, it would show no fatigue toxins at the end of the day.

So far as the brain is concerned, it can work as well and swiftly at the end of eight or even twelve hours of effort as at the beginning. The brain is totally tireless. So what makes us tired?   

    Some scientists declare that most of our fatigue comes from our mental and emotional attitudes. One of England’s most outstanding scientists, J.A. Hadfield, says, “The greater part of the fatigue from which we suffer is of mental origin. In fact, fatigue of purely physical origin is rare.” Dr. Brill, a famous American scientist, goes even further. He declares, “One hundred percent of the fatigue of sitting worker in good health is due to emotional problems.”

    What kinds of emotions make sitting workers tired? Joy? Satisfaction? No! A feeling of being bored, anger, anxiety, tenseness, worry, a feeling of not being appreciated—those are the emotions that tire sitting workers. Hard work by itself seldom causes fatigue. We get tired because our emotions produce nervousness in the body.

结合语境选择恰当的词填在横线上，恰当的一项是  （       ）
①唤醒 ②信念 ③所以 ④引领 ⑤憧憬 ⑥不仅 ⑦勇气 ⑧还 ⑨因为 
人为什么要读书呢？书，可以   沉睡的心灵，可以   迷惘的灵魂。一本好书，就是一个崭新的世界。读艾青的诗歌，我坚定了不断前行的   ；读史铁生的散文，我鼓起了直面人生的   ；读托尔斯泰的小说，我充满了对精神家园的   ……读书，就使用麦管吮吸甘露，   让人欣喜，   让人着迷。

2007年10月13日，日本、美国、法国、英国、澳大利亚和新西兰在日本东京伊豆大岛海域举行联合海上军事演习，如图所示，若在演习中，离地H高处的飞机以水平速度v₁发射一颗导弹欲轰炸地面目标P，反应灵敏的地面拦截系统同时以速度v₂竖直向上发射导弹拦截．设拦截系统与飞机的水平距离为x，若拦截成功，不计空气阻力，则v₁、v₂的关系应满足（   ）

下图为“日本山河分布示意图”。读图，完成题。