以下哪项不适用于口对口或鼻或人做口的人工呼吸法（） A.伤者府卧 B.口部沾染毒物或

如图，在注射器中加入少量Na₂SO₃晶体，并吸入少量浓硫酸(以不接触纸条为准)。则下列有关说法正确的是

A．蓝色石蕊试纸先变红后褪色

B．品红试纸、沾有KMnO₄溶液滤纸均褪色都能证明SO₂的漂白性

C．湿润淀粉KI试纸未变蓝说明SO₂的氧化性弱于I₂

D．NaOH溶液可用于除去实验中多余的SO₂

胎盘附着部位的子宫内膜完全修复需到产后

A．2周
B．3周
C．4周
D．6周
E．10周

Jonathan James looks like just another kid about to graduate from high school. But this 19-year-old Swede is anything but ordinary, from the computer in his parents’ home he helps the US Federal Bureau of Investigation(FBI) find out the world’s most wanted cyber criminals.

Jonathan first made headlines when he and another Swede, Fredrik Bjoerck, found out the maker of the "Melissa" virus in March 1999. He came to the aid of the FBI again on May 7, finding out the suspected sender of the dangerous "I LOVE YOU" virus. The suspect was caught in Manila on May 8.

Jonathan’s special skills are in hot demand as officials around the world express alarm at the "virtual" crimewave. In between studying for final exams, hanging out with friends and refereeing his younger brother’s football matches, the quiet, gentle teenager also gives lessons on e-security to large companies. He reads a lot and exchanges information with other computer experts to know much about the latest tricks of the hacker trade.

Many companies have already tried to employ him, but he is not interested at the moment. Instead, he plans to begin law school in the autumn at Sweden’s Uppsala University and start up his own e-security company.

Although he works with the FBI now, his family insists he’s just "a regular kid". "Jonathan is a great kid, he has his friends and he does a lot more than just play with the computer, " his little sister Tessa said, adding that he helps the FBI because "he likes to help", not because he’s looking for fame and recognition.

When the world was hit by the "Love Bug" virus, Jonathan was too busy preparing a speech on e-security to look into the problem. "Finally on May 7, I had some free time, so I began looking. " Within a few hours, he had found the suspect and e-mailed his method and results to the FBI. He said his work on the "Melissa" virus, which took three weeks to solve, was a big help in finding the suspect so quickly. "This time I knew exactly where to start, I knew what to disregard and what to look at.

The passage mainly wants to tell us that（）.

A. Swedish kid helps FBI find out the most wanted cyber criminals

B. Jonathan is really a quiet, gentle and ordinary boy

C. many companies want the young computer expert to join in

D. any cyber criminals will surely be found out wherever they are

汇总转账凭证

已知某教务管理系统有下列关系模式(带下划线的属性是主码)：
系(系号，系名)
学生(学号，姓名，性别，入学日期，正常毕业日期，所在系号)
课程(课程号，课程名，学分，开课系号，教师号)
选课(学号，课程号，成绩)
教师(教师号，姓名，职称，所在系号)
①请根据给出的关系模式画出该系统的E-R图，图中忽略实体集的属性，但如果实体集之间的联系有属性则需要给出联系属性。
②随着教学改革的需要，该系统需要满足下列需求：

需为课程增加先修课信息(一门课程可有多门先修课程)；