第二课的全面考试。问题会从测验2.1、2.2、2.3、2.4随意选取。每一个问题值一分，就是它有多数答案也是如此。时间:30分钟。
Time limit: 30 mins
Grading method: First attempt
Sorry, guests cannot see or attempt quizzes
Would you like to log in now with a full user account?