赫尔希和蔡斯通过T2噬菌体侵染细菌的实验证明DNA是遗传物质,实验包括六个步骤: ①噬菌体侵染细菌 ②用35S或32P标记噬菌体 ③上清液和沉淀物的放射性检测 ④离心分离 ⑤子代噬菌体的放射性检测 ⑥噬菌体与大肠杆菌混合培养。最合理的实验步骤顺序为. A.⑥①②④③⑤ B.②⑥①③④⑤ C.②⑥①④③⑤ D.②⑥①④⑤③1.A.worked hard at B.do better in C.by himself D.happy E.learn magicF.movie G.are crazy about H.surprise I.successful J.showLiu Qian is a magician(魔术师) from Taiwan.For the CCTV Spring Festival Gala(春节联欢晚会) he put on two magic shows.They were very (53)I.Now so many people (54)Gmagic.We all want to know how to do a trick!Liu didn't go to any magic-training school.He learned (55)C.He (56)Ait.Now he is a great magician.When Liu was seven,he saw a coin trick in a big store.At that moment Liu decided to (57)E.Liu trained hard to (58)Bhis skills.Then one day he was able to put on a show for his class."I saw the (59)Hon everyone's face.It was cool."Liu still does his training hard today.He may spend three years working on a new (60)J.