A:甲是a-t图象
B:乙是s-t图象
C:丙是s-t图象
D:丁是v-t图象
直线x-y-1=0的倾斜角是( )
“杯酒释兵权”的故事反映了北宋建立后( )
—You just have ___________. Wait until you finish this competition.