由甲苯制取2,4,6-三硝基甲苯(TNT)的反应属于 [ ]
A.取代反应
B.加成反应
C.消去反应
D.酯化反应
答案:A
In the diagram above, points A, B, C, D, and E represent the five teams in a certain league in which each team must play each of the other teams exactly once. The segments connecting pairs of points indicate that the two corresponding teams have already played their game. The arrows on the segments point to the teams that lost; the lack of an arrow on a segment indicates that the game ended in a tie. After all games have been played, which of the following could NOT be the percent of games played that ended in a tie ?
司机有权拒绝吊运()、()等具有爆炸性物品。