题目

- There were already five people in the car, but they managed to take me as well.- It ______ a comfortable journey.    A. can’t be                                   B. shouldn’t be    C. mustn’t have been                          D. couldn’t have been 答案：D 如图，在棱长为2的正方体ABCD－A1B1C1D1中，M为棱BB1．的中点． (1)求平面A1DM与平面ABCD所成的锐二面角的大小； (2)求点B到平面A1DM的距离．