回答以下有关实验的问题

（1）常根据生物组织中的有机物与某些化学试剂所产生的____ 反应，鉴定生物组织中某种有机物的存在．

（2）鉴定成熟梨果肉存在还原性糖所用到的试剂是____ ，形成____ 沉淀．

（3）脱脂奶粉比全脂奶粉的脂肪含量低，不含淀粉．假冒脱脂奶粉有两种：一是用全脂奶粉冒充脱脂奶粉，二是用淀粉冒充脱脂奶粉．鉴定是否用淀粉冒充所选用的试剂是____ ．鉴定是否用全脂奶粉冒充所选用的试剂是____ ，其呈现的颜色是红色．通过以上鉴定，我们并不能完全肯定是正宗的脱脂奶粉，还必须用____ 对奶粉中的蛋白质进行鉴定．

（4）在观察DNA和RNA在细胞中的分布的实验中使用的染色剂是____ 混合液；____ 能改变细胞膜的通透性，同时使____ 中的DNA和蛋白质分离，有利于DNA和染色剂结合．

（5）____ 染液是将活细胞中线粒体染色的专一性染料，可以将活细胞中的线粒体呈现____ 色．观察线粒体可以使用哪一种材料____  （填“藓类叶片”、“菠菜叶肉细胞”、“人口腔上皮细胞”）

河西走廊是“丝绸之路经济带”的重要通道。阅读下图，回答

派卫青、霍去病出击匈奴。取得河西走廊，并设置敦煌、张掖等郡县的皇帝是（    ）

    I went with some colleagues from my office for a dinner in a very popular local restaurant. It was1business time and the restaurant was packed. We2found a table in a corner for three of us.

    As soon as we sat down, we heard a crash when a cleaning boy3the floor with all the plates he was carrying. There was_4and no one was saying or doing anything.

    In a flash I remembered my5many years ago. Once. I passed out in the airport because I had rushed there on my own on a(n)6_stomach I was7and taken care of by two strangers. Now this was my chance to8it forward.

    I ran to the young man's side immediately, turned him on his back and screamed for someone to9a hot drink. Soon people started asking if I was a doctor. I said I was not,10I was skillful at blacking out (晕厥).

    The kid soon opened his eyes,11what had happened. I12him by saying it was OK and I had had a13 experience. He had not eaten anything. I held the14_drink to his mouth till he finished it and sat with him till he felt OK. By then the15had arrived. I asked her to give the kid something to eat. I offered to pay.

    The manager was kind enough to refuse the16and agreed to make sure the kid ate before he went home. By the time all this was17_, it was getting late for my colleagues. Since we hadn't18anything yet, they decided to go home.

    I slowly walked home, not hungry any more, feeling19for the opportunity I pay forward the20I had received many years ago.

“山外青山楼外楼，西湖歌舞几时休。暖风熏得游人醉，直把杭州作汴州。”该诗反映的时代特征是（    ）

①AD⊥BD；②∠AOC=∠AEC；③BC平分∠ABD；④AF=DF；⑤BD=2OF；⑥△CEF≌△BED，其中一定成立的是（   ）